Another Airgun Blog

Benjamin Nitro Piston Pistol Carbine Conversion

2026-01-26T14:43:00.000-08:00

Was kicking around for a simple project the other evening and remembered that I had a Benjamin Nitro Piston pistol. Years ago, this model was reviewed on the Pyramyd Air Blog and Gaylord mentioned that it might make for a nice carbine. Thought I'd finally make that happen and see if it would somehow transform what I think is just a mediocre pistol into a world-beating, shining-star, short-barreled rifle--and actually shoot it a little bit in the process.

Gas sprung in all it's glory. The Benjamin NP pistol is big, heavy and relatively powerful for its size. Initially, the pistol's accuracy was abysmal though after putting in some effort and fixing the almost non-existent barrel lock-up, it now shoots to point of aim all day long. So, now it's just big and heavy.

For the carbine conversion, I'm just going to make a quick and dirty adapter for my modified AR15 buffer tube(s). IF it pans out, I'll probably remake a cleaner version.

Added an M5 threaded hole to the end cap.

Found a slice of 1" OD aluminum tubing and made a short adapter:

Adapter bolts to the threaded hole in the end cap.

My modified AR buffer tube is then attached with a socket head cap screw to the adapter. Maybe there doesn't need to be a cleaner version.

Since I mounted a pistol buffer tube, here it is with a Strike Industries pistol brace.

Doesn't get much simpler than this. Unsurprisingly, it cocks even easier than before using that stock as leverage. Shoulders quickly and the red dot is easy to acquire.

Well, it's still not something that I'd pick to shoot all day at paper targets, but with a reactive target like a swinging steel silhouette, its a fun afternoon. Sometimes that's enough.

Vacation Time with the Air Arms Pro Sport

2025-10-10T07:17:00.000-07:00

Just checking in.

Spent the last few days in the George Washington National Forest on the Virginia/West Virginia border. Of course, we brought air rifles. This week is always an opportunity to bring out some airguns that don't otherwise get much play time.

Brought the .22 Pro Sport that I've had for almost two decades. Not sure I've ever shown it on the blog before. Set up with a 4-12x Swift AO scope and an Outdoor Connection Super Sling.

Had a great time smacking spinner targets all week with an absolutely drop-dead gorgeous rifle.

The Restocked Remington Summit Follow-Up

2025-09-28T11:39:00.000-07:00

This is more of a "where are they now?" post along with some rambling backstory.

Looks like a Benjamin Trail NP2. Except there's no gas ram. I shoehorned a Remington Summit (Sold by Crosman) spring piston action into that stock five or six years ago.

Here's what my Summit looked like in the original Remington stock. Glossy! The Summit was an entry to mid-priced .177 caliber break barrel made in China. It was probably rated at 1000+ fps or something similarly ridiculous. And it was glossy. Really, really glossy. But, it was also super easy to cock and shoot all afternoon and that made a fine first impression.

Purchased years ago from Chuck at Precision Airgun -- both sadly now gone. This was a factory refurb from Crosman who owned the Remington air rifle branding rights at the time. I liked the clean lines and long forend covering the pivot joint. Didn't like the high gloss, but figured I could always strip it and do a matte finish later. Besides, it was cheap. Maybe $100 including a plain steel muzzle weight, scope and mount.

Initially, I remember the rifle did have some lock-up issues. It was inconsistent --a bit vague when the barrel clicked home An overhaul of the power plant, replacement of the plastic pivot shims and a stronger detent spring solved all of the mechanical problems and then some. The Summit's accuracy turned out to be better than its price or pedigree would've indicated.

There was never a plan or specific role for the Summit. The rifle got hand-me-down parts from other projects. I'd throw on a different scope or muzzle brake, shoot it for a week, admire its accuracy, then set it aside. Several years later, I noticed mister glossy was cracking and I sourced what I had hoped would be a non-glossy, drop-in replacement stock from Crosman. It wasn't quite that simple--I linked to that a few paragraphs back-- but getting it back in action was worth the effort.

After several years now in the new stock, the rifle has changed very little from the original set up.

The plain Jane factory steel muzzle weight was traded for an early, now vintage, ported brake from Vortek. In the 1990's, we thought these Vortek muzzle brakes were the height of aftermarket airgun coolness on our R1s and R10s.

The Bushnell 4-12x with an adjustable objective lens is probably mid 2000s vintage. Probably a Banner model. Definitely an eBay acquisition. This is not the scope originally packaged with the Summit. That was a Crosman labeled 3-9x with AO and is currently serving on Volvo's QB78.

A Charlie Da Tuna trigger. GRT-III

UTG 11mm dovetail to picatinny rail adapter. The Summit originally had a single scope stop pin hole in the spring tube. I'd drilled another at some point, but was still rather limited in setting up the eye relief. This adapter centers on the dovetails and doesn't introduce any lateral offset.

One thing I've come to appreciate is modifying/reworking some of my air rifles. It largely satisfies my desire for a new gun without buying yet another. And I end up with something a bit more interesting (at least to me) than an off-the-shelf rifle. To that end, I'm leaning toward stripping the stock and giving it a nicer finish. And I don't mean glossy.

We'll see what shakes out.

Modified CO2 cap with a QD Sling Swivel on a Crosman Carbine

2025-08-10T08:30:00.000-07:00

I'm always changing configurations with my various Crosman 22XX guns. Their modular design makes it easy to go from pistol to carbine to rifle and back in a few minutes. Combined with a few adapters, I've been able to try several interesting combinations. In the last blog post, I had thrown together a .20 caliber carbine and wanted to use a vertical fore grip from Magpul. Assembled, it felt pretty good, but there wasn't a spot for a front sling position. Granted, a single point rear sling worked just fine, but most of these projects come about from trying to solve a unique problem.

A bit of head scratching and I thought a QD front sling socket could be incorporated into to a modified gas tube cap as an inconspicuous attachment point.

Rather than butcher the original cap,

Started from zero with a piece of 7/8" diameter 12L14.

Turned the end down to about .8085"

And threaded with a very uncommon 13/16 - 28 die to match the Crosman 22XX gas tube.

The camera angle is bad, but I used a thin parting blade to cut a relief at the end of the thread.

Since I'm using the Crosman mid-length 2250 gas tube, the cap will need an extension to bear against the end of the 12G CO2 cartridge. Might as well plan ahead for the three different Crosman gas tube lengths--2240, 2250, 2260.

A #3 drill is the correct diameter--

for a 1/4-28 tap.

Just Some Pics of my .20 Caliber Crosman 2050

2025-06-07T12:06:00.000-07:00

Apologies. Not much to report lately. Some tinkering here and there, but nothing I've found interesting enough to blog about.

I did swap one of the Crosman 2250s over to .20 caliber. Didn't take any pics of the conversion. Just a basic barrel swap--though I did try to make it look like a cohesive assembly. Converts to a lightweight carbine in about a minute using a Strike Industries pistol brace. I didn't have a red-dotted carbine, so it fills a niche.

Quiet and easy to shoot. What's not to love?

Feinwerkbau 124 Sling Attachment -- Part 2

2025-03-05T17:55:00.000-08:00

Picking up where I left off, I still needed to make that shorter cocking lever rivet and lose those two aluminum washers.

Pulled the action out of the stock and tapped out the cocking lever rivet. As a reminder, the aluminum washers had been added to replace the space taken up by the original factory sling swivel. At the time, those washers let me reuse the original rivet without any further modifications.

In the last post, I waffled around and settled on making a quick scope stop because I couldn't decide how to make the replacement rivet. Sure, the rivet is a simple project--except I didn't want to pein or mushroom the ends of the new rivet. Technically, I guess that means I'm actually going to make a pin. Then, I couldn't decide whether to use a piece of 5mm drill rod and cut grooves for e-clips or turn down part of a larger diameter leaving a head on one side? Too many options for a guy like me. Actually none of this was really slowing down the project. I simply didn't have a grooving tool thin enough for a small e-clip--and I had no experience cutting e-clip grooves. I got stuck looking at groove specifications and wonder how I'd accurately measure the diameter in that thin slot? Did I have any e-clips that are suitable? Then I backed up and wondered if an e-clip was even the right solution for the project? I did mention my catastrophizing in the last post.

Eventually, I did some research on machining e-clip grooves, figured out how they're supposed to be sized and toleranced, bought a bunch of e-clips, then procrastinated for another week until I could find time to go work in the basement. About then remembered I still didn't have a grooving tool this small.

Started anyway. A piece of scrap 3/8" diameter O-1 tool steel went into the Taig lathe. Flanged pin design wins. The deciding factor? This only requires me to cut one e-clip groove.

Body of the pin needs turned down to about 0.1965"--just barely under 5mm.

Now I needed a groove for this guy. I believe this is a 4mm e-clip--4mm referring to the OD that it clips over.

I had to grind a tiny grooving tool--0.030" wide from high speed steel. The width of the Feinwerkbau's base block was 0.590", added about 0.005" to that number, and plunge cut the groove 0 .595" -- 0.596" from the inside face of the shoulder.

Measuring the diameter was giving me trouble. Had a hard time getting a repeatable measurement with the caliper in that .030" slot width. I finally gave up and just used the clip itself as the gage. Tried to get it to snap into place. No go. Took a few more thousandths and tried again. After a few test fits (and a few mangled clips) the clip installed and wasn't distorted after removal. Called that good.

I need to shorten the end a bit more.

Then flipped the pin around and thinned the 3/8" diameter head down to 0.095" thick.

And there it is. All this procrastination for this. Well, this and that little scope stop.

If it was still 1991, Doc Beeman could've sold something like this in his catalog. "Designed by my wife to upgrade your FWB124 to take modern slings. Its exquisitely delightful." That'd be the gist of it.

Blued the ends that'll be visible.

Almost seated. A wood block smacked it home.

And the e-clip snapped right into place.

Good clearance with the longer forearm of the stock.

I like that I can now use a "normal" 1.25" sling with standard hardware on my old rifle. I'm also pleased that it doesn't look like I was involved in any Feinwerkbau gunsmithing shenanigans.

And just for fun, here's the "delightful" scope stop again from the last blog post.

More soon.

Feinwerkbau 124 Sling Attachment and Scope Stop -- Part 1

2025-02-22T13:08:00.000-08:00

This old Feinwerkbau 124 was my first air rifle purchase. Think I was sixteen or seventeen at the time. I'd been reading the Beeman catalogs and wanted something decent. The R1 had come out recently and wasn't in this kid's budget, but the FWB 124D in the used gun rack certainly was. Several decades of repairs/upkeep/changes and modifications led to its current set up. Probably the most significant improvement was the hand made walnut stock from GunBroker. The stock was made by Serban Ionescue. It's a beautiful thing. The lines are so graceful and unique.

While shooting this the other day, I remembered I hadn't actually finished the replacement stock installation. Sure, the rifle was shootable, but it wasn't "done". At the time, I'd done a make-do arrangement with what used to be the built-in front sling loop and I neglected to install a rear sling stud. I actually had a rifle with no way to attach a sling.

And all I needed was a barrel band clamp and a screw stud?

Dug through the collection of pieces and parts, but didn't find that necessary screw stud. A quick trip to the local "gunmart" was fruitless. They have a Glock section, a Smith and Wesson M&P section, all the Magpul gagets and a bunch of employees who won't even pretend to help. Was really a great experience. Went home, ordered a ten pack off ebay and checked it off the list.

A week later, I was awash in sling studs and trepidation.

Installing this little guy gave me great anxiety. The stock was beautifully finished. Was I about to ruin it? Would the stud be centered? Will the walnut splinter, crack, and tear? How many bad sling mounting jobs have I seen in the used gun racks at any given gun show?

Eventually, I'd checked, double-checked, re-checked, then double-re-checked everything--especially the drill bit size. And in a couple minutes, it was done and all my worry was for nothing. No, that's not really true. All my worry identified the potential problems I would run into during the installation and helped prevent them. Catastrophizing is often my super power.

The front end of things was less of a challenge. I found an Uncle Mike's barrel clamp for the front attachment point in a drawer--probably purchased and set aside years ago for this very project.

Just like that, the old girl was finally wearing a 1.25" Outdoor Connection Super Sling+. While a leather sling might look more appropriate, its tough to beat the quick adjustability of the Super Sling.

Now, here's the rest of my unfinished business. The original FWB front sling swivel had to be removed because its flared width wouldn't fit through the longer forend of the new stock. I'd quickly installed a couple aluminum washers on either side of the rivet and said, "Good enough, I'll figure this out later".

Here’s the removed FWB sling mount.

The way it flares out at the bottom prevents it from fitting through the new stock’s extended forend. The shorter factory stock doesn’t come far enough forward to be a problem.

Of course, at the time, I was far more interested in getting the action into that gorgeous stock. Besides, that original FWB mount was only sized for the old skinny 22mm (7/8") carry straps.

And then the plan came to a screeching halt and I opted to make a scope stop instead. Yes, a scope stop. Why? No good reason, but follow the squirrely logic: The gun shoots fine and now wears a real sling --so I can live with the aluminum washers for another day or two. A quick and dirty scope stop sounded far more appealing. My continued procrastination made sense at the time.

Yep, a scope stop it is.

As the Feinwerkbau was wearing UTG dovetail mounts, I wanted the scope stop to look like it was made to match. Found a UTG offset mount and cut off part of the clamp.

I like projects with the least amount of resistance. (I later added another mounting hole to that sacrificial mount so it's still functional.)

Cleaned it up in the milling machine.

Just needs a second clamping screw. I can't believe I've never made a scope stop before.

Tapped M5 to match the other thread.

Not shown: As conventional stop pins don't fit 124's, I wasn't going to drill and tap for one, but the practicality of having it won out. Now, it's compatible with most of my other rifles.

With no stop hole in the 124 tube, some friction paste will have to suffice.

Matched and replaced all the mounting hardware for continuity.

A plug screw fills the hole.

Looks like a good match and I've successfully put off making a cocking lever rivet for another day!

More soon.

#4-48 Breech Screws for Crosman

2025-02-03T17:08:00.000-08:00

Just a quick post tonight.

The other day, I was taking apart a Crosman 2240 pistol and I thought the ~~stupid~~ tiny #4-48 breech screw should be replaced. I went to my spare parts and found I was down to two. Used to buy these screws right from Crosman, but with the Daisy/GAMO buyout, I think that option is now gone.

With all the Crosman CO2 guns around here, figured I'd better come up with a new source.

Let's face it, #4-48 just isn't a common fastener size. Crosman was essentially forced to use such a fine thread due to the thin gas tube wall thickness. To make it even harder to source, Crosman spec'd a low profile head--pretty much guaranteeing that this is a custom fastener. These just don't exist at the local hardware store/home center.

That micro 0.050" hex wrench is icing on the cake for a bad experience. Over torquing the tiny fastener--or wrench-- is pretty much inevitable.

Yeah, I pretty much hate this fastener. I usually treat these screws as single use. I'd much rather burn the dollar they cost than have to remove a stripped, stuck screw in a gun.

In an effort to solve my shortage and not have to think about this again--at least for the forseeable future--I bought a 25 pack of #4-48 BUTTON HEAD CAP SCREWS from McMaster-Carr.

Of course, the button head is a bit too wide in diameter to fit into the counterbore in the Crosman breech.

Here's the button head vs. the low profile socket head.

The button head is about 0.208" diameter vs. 0.180" of the original Crosman spec.

Made one of my fancy thread holders.

And a #4 nylon washer for standoff.

The Taig lathe makes short work of problems like this.

In a few seconds, the head diameter was reduced to a functional size. Don't need to hit the 0.180" diameter to the exact decimal. As long as the head fits the counterbore recess of the breech, it'll work.

Since I was still feeling all fancy from making the thread holder, I blackened the head and called it good.

As a marginal benefit, the button head fastener takes the next larger 1/16" hex wrench. The (.0125") larger wrench size feels gigantic in comparison.

No lathe? I just chucked one of these screws in a DeWalt cordless drill and reduced the head size with a small file in a little over 3 minutes.

More soon.

Volvo’s QB78 Deluxe CO2 Tanker Rifle Part 5

2024-12-30T16:38:00.000-08:00

I've got the QB78 pretty close to what I'll call finished. The gun's been holding CO2 for weeks now. It's scoped with a 3x9. The sling can be attached in a couple different ways. The various accessories plug into the t-track.

Used a modified KeyMod QD fitting to attach the sling at the butt. Could've used a conventional sling swivel stud, but this makes a couple of my rifle slings compatible without changing any hardware.

Sanded/filed a small flat and drilled a couple holes.

Revisited the mounting bolt. I didn't like that I had recessed the original bolt. Having it flush to the bottom of the forend seems cleaner.

This is a modified M-Lok QD fitting. Can be slid fore and aft along the T-track.

Going out of my comfort zone, I thought I'd use this as an opportunity to try a scope eyeshade. I've managed to acquire three of these in different sizes over the years--and I can't remember ever trying one before. To be honest, I can't remember ever actually buying one either. Anyone have any input about using one?

Made a pin for the magnification ring. Easier to thumb than the small plastic protrusion.

Some parting shots.

I could be convinced to add an adjustable butt pad. It wouldn't take much. Anything that improves shooter fit to the gun is worth the trouble. I could also be cajoled into refinishing the stock once spring rolls back around. Though for now, I'm just going to shoot it. I love that it can be set up in a couple minutes to use a 12g cartridge, a 90 gram AirSource, the Czech CO2 tanks from my Aerons or any of the 9 oz paintball tanks on hand. Being able to slap on a bipod or a hand stop is also really convenient. Expect that I'll leave a small bipod on this rifle. Very pleased that the rail installation didn't require any additional stock repair. Gonna call that one a small victory.

Happy New Year everyone.

Volvo’s QB78 Deluxe CO2 Tanker Rifle Part 4

2024-12-01T07:39:00.002-08:00

Been shooting the QB78 Deluxe for a few weeks now. Shooting offhand, I found that it was a bit too front heavy with the paintball tank attached--more so with the paintball tank and the Rich From Mich moderator. In an effort to lose the weight of the tank, tried both a 12g dual adapter from Umarex as well as a 90g AirSource CO2 cartridge. The modified valve in the QB went through the CO2 in the dual 12g adapter at a record pace. Maybe 20 good shots? The 90g AirSource cartridge seemed a better compromise between weight/balance and a reasonable shot count. Removed the moderator and installed an even quieter combination shroud/moderator I had on hand. Yeah, there was some minor machining to make it fit... This dropped and shifted the weight so it wasn't all cantilevered over the front end. With the balance changed, now I wanted options. I want to be able to quickly set this up for various roles.

Of course, a rifle sling was mandatory. On a PCP or CO2 rifle, aside from making the gun easier to carry, the sling can actually be used as a shooting support.

This is a sling attachment I made a few years back to fit 88/90g AirSource tanks. It fits over the M16x1.5 tank threads. Can also see how the rear of the shroud is attached with set screws to the QB barrel.

Front of the shroud has 1/2-20 threads for this carbon fiber moderator.

Picatinny rail is always convenient. Well, it's usually convenient. I should know better by now to not use these polymer rails. They're OK for sling or hand stops, but marginal for bipods. A bit too flexy and twisty for me. Had I just gone with an aluminum rail initially, I might have been tempted to call it good enough.

But this was not what I really wanted.

Still had some t-track rail from the QB I converted from .177 to .25 caliber. No, it's not a UIT/Anschutz rail. While I've used those in past projects and acknowledge that they seem to work fine, I've never been thrilled with using one as the mounting base for a bipod. This piece of t-track from Rockler Woodworking & Hardware uses a much thicker, more substantial nut than the Anschutz rail. Since I can mill the t-nuts, it becomes relatively easy to make a half dozen with both 4 and 5mm threads. I can attach anything to this rail. Anschutz, M-Lok, KeyMod, Picatinny, Any type of sling mount, hand stop, barricade rest, forward grip, bipod, tripod...can all be made to work with this rail in a few minutes.

Here's a slice of t-track that I've already started to fit. The only real downside is the work involved to inlet the stock. At least I have milling cutters in the same 3/4" width as the rail.

Media blasting got the red out.

The biggest hurdle in fitting the rail was the stock's shape. Couldn't get a grip on the tapered sides. I tried multiple combinations of tapered shims. Nothing was particularly promising. It's 25 degrees F in the garage right now. Rather not damage the rifle's finish, as I won't be able to fix it for four more months.

Eventually my squirrel brain realized there was a simpler solution. Bolted and screwed on a block of wood. The bolt is through the existing hole for the locator stud. The screw went into wood at the bottom of the barrel channel. Nothing visible after reassembly.

The block gave me something parallel to grab in the milling machine vise.

With a straight edge, I leveled the forearm as best as I could.

Centered up.

These set ups are best efforts. The wood stock isn't straight within 1/16". The curves aren't perfect. If I have to do this again, I'll take the full depth in one pass.

There was a small surprise. Notice the void in the wood. There's still some wood putty visible. Never saw this from the outside. I'll fill this with superglue and fine sawdust.

The mill needs a vacuum attachment.

Of course, test fitting as I go.

The brown colored Sharpie marker was almost a perfect match to touch up the edges.

Call it camouflage in case any of the edge is visible.

There's the superglue filled void.

The screw cup got uncolored to match the accessory rail.

This curve was another best effort.

Marked the high spots to blend the rail into the stock.

Then some mounting holes.

Countersunk. These screw heads need to be flush--or below--for the t-nuts to slide freely in the track.

Smoothed out the finish on the accessory rail.

Polished with a block of Cratex.

Cratex is a rubberized abrasive--a big rubber eraser charged with silicon dioxide.

Wow. All that work for this. At least I managed the fit without mangling the factory finish. Now I've gotta go get some Christmas decorations out.

Need to redo the rear sling mount and get some better pics up.

Volvo’s QB78 Deluxe CO2 Tanker Rifle Part 3

2024-11-12T17:41:00.000-08:00

Working my way through Volvo's QB78 Deluxe. I keep wanting to call it a Tech Force, probably because my AR2078a carries that name laser engraved on the breech.

Here's what I've been doing:

Cleaned up then blackened the aluminum riser plate.

Made a new bolt handle from a piece of tool steel--with 1/4-20 threads as I've done before.

The old bolt handle.

And here's the new handle again with a 1" rubberized ball. Spoiler. The rubber ball handle is a fail.

Then spent a few minutes deburring the barrel shank o-ring grooves.

Softened all the sharp corners that were chewing up the o-rings.

Recut the crown.

QB78!

My old friend, flex hone.

This is the easiest way to clean up and remove all the burrs left from the machining.

Original locator stud and stock nut had to go. It's not you, it's me. It's me not having a suitable notched peg-spanner on hand making this so damn inconvenient every single time the rifle is taken down. It's you for not being a commonly encountered fastener. It's definitely you.

This is what I went through to make my life easier.

Found this in the scrap box.

A 1/2" diameter 6061 aluminum rod that already had M8x1.25mm threads in one end.

M8x1.25mm low profile socket head cap screw. LPSHCS.

And a scrap of 1" diameter aluminum for a screw cup.

The 1" diameter aluminum was first turned down to just slip into that gaping hole in the underside of the stock.

Shave a bit off, test fit. A bit more, test fit... Measure? Bah. I had enough aluminum to wing it.

Through drilled with a 5/16".

Counterbored for the head of the 8mm fastener.

Parted off.

Cleaned up, deburred, chamfered.

Checking fits and clearances.

Through hole in the stock is too small to take the 1/2" aluminum rod.

Carefully lined up the existing hole on the milling machine.

Changed bits and opened up the hole.

Here's the screw cup.

Yep.

Bolt will fit like this...

Still didn't feel like measuring. Slid the 1/2 aluminum rod through the stock until it bottomed on the screw cup. Grabbed that Sharpie marker in the background and marked the rod where it'll stop against the gas tube.

The rod will need to be approx 1/8 to 1/4" shorter than this marked length.

Cut and faced the rod.

Drilled and tapped M6x1mm.

M6x1mm Socket head cap screw. SHCS

Cut the head off. ~~SHC~~S

Into the 6mm screw holder.

Some Loctite.

Now I have an oversize locator stud.

The 6mm thread screws though the gas tube and retains the valve retainer ring.

The 8mm end fits the stock bolt.

Detour.

Dropped the cocking pin from the hammer. Heard it bounce and roll. It still hasn't turned up. Made a replacement.

Back on track for my project to make the stock nut "convenient". The irony isn't lost on me.

OK, the LPSHCS stock nut and a couple really thin steel washers.

Assembly time:

New o-rings for the barrel shank.

Installed the bolt with the rubber handle that doesn't make the cut.

Trigger unit

Tank block, barrel band & barrel.

More new fasteners.

There's the end of the 1/2" locator stud. Just barely recessed below the counterbore.

Sometimes this works OK. Sometimes nope.

Looks good.

Then I tried cocking it and remembered why that rubber ball bolt handle didn't make the cut with my AR2078A.

The "Cock on Close" operation of the bolt action leaves a little to be desired. It's awkward biomechanically. The rifle is off your shoulder and you shove the bolt forward against spring pressure as you try to hold the rifle stationary. When the bolt is completely forward, you rotate it down to lock it closed. That soft rubber ball squishes and flexes as it adds vagueness to the awkward cocking motion.

Try this again:

Sorry, no unboxing video, it came in a bag.

Steel. 1/4-20 threads. McMaster-Carr.

Blackend.

This essentially got the rifle assembled and functional. I didn't really do anything additional to the trigger except replace the blade.

Still figuring out sight options and need to send more pellets downrange. Volvo likely had a specific role in mind for this rifle. I'm thinking it was backyard garden pesting in the suburbs. I'm considering some alterations to better fit my needs and add more convenience.

I'll have something up in a couple days. Thanks for checking in.

Ferritic Nitrocarburizing for Airgun Parts

2024-11-07T17:10:00.000-08:00

Sidetracked by FNC? Yes. Yes I was.

An opportunity came up to have some of my airgun projects professionally finished. Extra space was available in a batch of parts last week. The parts were to be Ferritic Nitrocarburized--a hardening and blackening process that chemically alters the metal surface with additional nitrogen and carbon. FNC is also known as Melonite or Tenifer. The finish is similar to a case hardening. It's done in a molten salt bath at approximately 1000 degrees F that hardens the surface and makes it both highly wear and corrosion resistant.

H&M Metal Processing in Akron ran the job. Their website has a good description of the process.

I sent a couple barrel sleeves for break barrels and my multi-shot breech. The previous cold blue jobs I had applied look good, but will wear through in spots after enough handling and require rework.

But first, I had to undo all the time spent bluing and take the parts back down to bare steel. There was a bit of hesitation. I didn’t exactly know what to expect from the FNC treatment. Would the finish be uniform? Aren’t the parts already good enough? Steeled up my courage and minutes later, the parts were back in the white.

And then they were in a box and out the door.

A day later, the driver showed up and the parts were done. Oily, but done.

The parts are dark black— like a black oxide finish. But now they’re black and around 64+ Rockwell on the C scale. It’s unlikely the finish on the barrel sleeves will ever wear again. The treatment sounds ideal for a break barrel air rifle.

I’m thrilled with this process. Aside from a fresh abrasive blast to remove the cold blue, I did zero prep work. This was a very last minute opportunity.

If/when this comes up again, the barrel sleeve on the Weihrauch 35E will be next in line.

Back to the QB78 re-seal real soon.

Volvo’s QB78 Deluxe CO2 Tanker Rifle Part 2

2024-10-30T17:52:00.000-07:00

After too much internet hunting for this air rifle's exact model name, it turns out Volvo simply mixed and matched a bunch of parts from Archer Airguns. So there you go.

Anyway, the CO2 was coming out as fast as it was going in, so I did some tear down. We've covered the repair of the almost identical models in detail cataloged under AR2078A, Crosman 160, Crosman 180, QB77, QB78, TF79. Find those blog posts using the index on the right of the page. —————————〉

Note the thinned bolt probe for more gas flow. This is courtesy Rich From Mich.

The second barrel set screw looks like it was added by Rich.

I don't know the origin of this riser plate. I'm not seeing it on the current Beeman version of the rifle. Thinking Rich machined this for Volvo so a 9oz paintball tank would clear the barrel.

The ice maker tubing transfer port trick.

Reference photos to help with reassembly.

Finally, the valve. And I don't have a valve wrench for this one.

Scrap of .750" DOM tubing.

JUST fits into the gas tube.

I made a quick valve tool. The long cuts on the sides of the valve are one of the tricks used to help increase gas volume--and velocity.

Valve body o-ring looked like it was starting to go.

Don't think this is an original valve stem. Looks like it was custom made from PTFE or acetal.

Some valve body o-rings.

A shot of Crosman pelgun oil for the seal.

On to the trigger. Light pull, but there was something dragging in the initial movement. Felt like it was clicking.

I'll do some polishing on sear faces later. The dovetailed trigger blade is amazing--why bother with the additional machining steps?

Small metal chip in the trigger. Clicking gone.

This is the old trigger from my (also old) QB77. Just gonna swap it in and see if it's a fit.

Fits!

Replace with a hex head.

The o-rings on the barrel shank are torn up as they always are. Front end of the breech usually has some sharp and snaggy edges that shave the o-rings twice--every time it's assembled and then disassembled.

The offset drop block for the tank. This offset is necessary for a paintball tank to clear the underside of the barrel.

That o-ring has seen better days.

Cracked in several places.

This is a normal o-ring failure in a CO2 gun.

Replaced with some viton o-rings.

One of the two M4 screws holding the drop block to the gas tube.

The original fasteners seem to be made of some pretty soft steel. I'm swapping these out for better fasteners as I go.

Here's another M4 fastener that anchors the stock to the drop block. These also got swapped.

Except there was only ONE replacement in black oxide in my fastener collection. The right side gets stainless steel for now. Kind of a non-genetic caused heterochromia? Sorry, it's getting late.

Some CO2 options below:

AirSource 88/90 gram CO2 cartridges work with an adapter.

This thing turns two 12g cartridges into an AirSource. If that actually makes any sense.

Got it all back together and gassed it up. Now, I'd like to give it a few days to make sure it holds before I start fiddling.

Volvo’s QB78 Deluxe CO2 Tanker Rifle Part 1

2024-10-22T08:51:00.000-07:00

World-renowned and all-around good guy, Volvo, kindly gave me an air rifle recently. A CO2 rifle he'd tried but apparently never really bonded with. It had developed a leak and he figured I was the guy to fix it and give it a new home.

It's a QB78 Deluxe (Industry) branded rifle. Volvo purchased it several years ago from (now retired) "Rich from Mich". Rich tuned and sold airguns as well as made custom machined accessories.

This particular rifle is difficult for me to find a specific model name. The rifle has been sold in a dizzying array of possible stock, sight and CO2 source configurations under at least three brand names--QB, Tech Force and now Beeman-- and in both .177 and .22 caliber. With five or six different stock options, sporting or diopter target sights and a couple different triggers, there have been a multitude of model numbers. The base gun is an almost identical copy of the Crosman 160/167 that was made from 1962 until 1971. The base gun utilizes two 12g CO2 cartridges. Options to pressurize include dual 12g CO2 cartridges, bulk-fill CO2, CO2 paintball tanks and now high-pressure air.

Volvo's rifle is an interesting combination of features: a match style target stock, .22 caliber, paintball tank compatible and a custom Rich from Mich shroud/suppressor. As I attempt to navigate the various model names, I THINK that makes this gun similar to the current Beeman AR2079A-- but with the suppressor instead of the target sights. However, the gas tube is laser marked QB78, so it was probably a custom assembly to meet Volvo's spec.

Regardless of the model, he had this set up as a quiet pesting rifle that would get hundreds of shots from a paintball tank.

The base model gun is used as a modular platform to build whatever you want. I've got a ~~couple~~ several set up at different ends of the spectrum that have all been covered here in the blog. One as a 10-meter style, bulk fill, match gun in .22 caliber. The second, as a bulk-fill .25 cal scoped precision-rifle style build.

Ok, yes, there's a third--also have an old Crosman 160. Anyway, there's a reason some shooters flock to this rifle platform and often build half a dozen different iterations.

Some additional pics and some likely modifications:

The stock nut takes a special wrench that I can never find. A hex head fastener would be so much easier for me.

Probably want to change the bolt to something not gold.

Swap the phillips to hex heads and make some screw cups.

Volvo's version of the rifle has a drop block with a CGA320 female thread. The drop block offsets and allows a paintball tank to clear the barrel. The CGA320 is a standardized gas connection designation that includes the thread size (1/2-14 British Pipe Straight), the counterbore dimension for the tank's o-ring seal and the pin to depress and open the tank valve. I really like this feature. Hundreds of shots with a paintball tank. Hundreds.

Wondered if the moderator was permanently bonded to the barrel?

Closer examination. The black finish of the moderator looks like a vinyl wrap decal.

The two small holes conceal set screws underneath that secure the moderator to the barrel.

Volvo's set up is pretty close to my vision for the rifle. Handy with lots-o-shots.

I'm at the fun part of the project. Going through boxes of squirreled away airgun widgets and gizmos trying to see which combination stands apart. We'll see what shakes out.

Vacation Airguns Part 2

2024-10-18T18:00:00.000-07:00

Nothing much, just a few additional airgun pics from the Pennsylvania trip.

Still wanted to shoot the B26-2 a bit more. I've mentioned that it fits me like it's been tailored?

Of course, I brought the Crosman 2260AR project gun for my wife. She loves the light weight and easy accuracy. Yeah, I probably shot it 2X as much as she did.

MFT stock on a modified mil-spec buffer tube.

P-Rod forearm modified to fit.

Vaguely recall making this stainless steel safety. There's a two stage Crosman trigger in there.

The bead blasted grips and forearm.

Love/Hate relationship with the scope? It's an older model NCSTAR fixed 4X. It's their copy of the Colt carry handle scope. Removed and threw that mount away and got these 35mm(?) rings.

Love that the scope hold zero and the bullet drop compensator is actually useful. Hate that there's no quick adjustable objective--though it will focus on the rear eyepiece with some fiddling.

Guess it's more of a Love/Meh

And the Marksman 56 got some additional pellets down the bore.

Hope to tear down a bulk-fill rifle very kindly given to me by Volvo a couple months ago. I've been thinking about how I'd like to set it up and what kind of rolls it can fulfill. Spent the last few evenings getting all the various accessories together and thinking about all the options and possibilities.

Vacation Airguns and Impressions From the Crosman 1322

2024-10-10T08:41:00.001-07:00

Probably a pneumatic first--at least for me. I brought the 1322 on our trip to the Laurel Highlands in Pennsylvania. I can't remember bringing a multi-pump pneumatic along on one of our vacations before this. Our trips usually have a similar theme; cabin in the middle of nowhere, hiking, lunch out on the trail then back to the cabin for some airguns and a good meal. Hiking plans, weather forecasts, and proximity to other properties always factor into which and how many airguns make the trip. This time around, we'd stayed at this cabin several years ago and knew it was ideal for shooting.

The red dot was a useful addition. The silhouette targets we bring get hard to find in the evening light, making iron sights practically useless.

The Adco red dot is nice and round with no flares. The short, almost stubby steel bolt handle seems just right to cock the hammer.

If you squint, or if I took better pics, there's an adjustable trigger stop at the rear of the trigger guard.

Two hex screws to remove the red dot. I'm tempted now to remove it then see if it returns to zero. My gut says it will.

For me, the conversion to .22 made this a lot more fun to shoot. Bigger pellets are easier to manipulate and load into the trough.

This 1322 has one other interesting feature to reveal.

There's no trigger spring.

Instead, I installed two small rare earth magnets. One on the base for the conventional spring and the other was bonded to the bottom of the sear. The magnetic poles face and repel each other. In practice, it feels frictionless.

Tried this sorcery several years ago and I'd all but forgotten to show it.

Hope to show a couple of the other guns I got to spend some time with.

While I don't expect to take any deep dives into multi-stroke Crosman 1377/22 madness with flat-top pistons, swept volume, dead space, etc...this pistol is very satisfying to shoot.

More soon.

Making a Set-Back Trigger and Trigger Guard for the Belgian Hy-Score 801 Part 2 Final

2024-09-16T17:35:00.000-07:00

Been working away on the Hy-Score 801 trigger and guard since that last blog post. The blogs make this stuff look like it happens in an evening. The reality is a bit more mundane, especially when I'm working on something out of my element. I had mentioned to co-blogger, Nick, that I had no idea how to form the guard--aside from clamping it in the vise and smacking it with a hammer. After my experience over the past week, nothing has really changed.

So, why again am I doing this to a 70+ year-old air rifle? Because the trigger is difficult to reach and seriously detracts from an otherwise wonderful air rifle.

Cut two of these strips of from 0.125" thick cold rolled steel.

Compared to the original stamped steel trigger guard, it's substantially thicker.

Didn't like the surface finish and didn't want to sand it for an hour, so I dusted the faces on a surface grinder at work.

At least it'll be shiny.

Clamped with some aluminum in the vise jaws to protect the finish.

Assumed this might help. I was wrong.

Nice. Now the steel was both sharp AND hot.

Nevertheless...

Version 1 was dead simple and provided me with the basic clearances for the set-back trigger to function.

Couple evenings later, I tried bending a second trigger guard--minus the heat.

Tried for a bit more curve.

More abrupt at the front than I wanted, but I think it better fits the svelte lines of the stock.

Both guards went to the milling machine to drill the mounting holes.

Not shown--chamfered the holes on the outer side.

Roughed the curves into the ends on the bench grinder then filed and sanded.

Versions 1 and 2

I suppose that either guard would actually be fine for a 70+ year old rifle.

Ver. 1 test fit:

Hmmmm... it's actually not that bad.

Test fitting Ver. 2

Think the lines of #2 are a better match to the rifle.

Going to finish both guards. More filing, sanding and polishing. Most of the time was spent rounding off the bottom edge.

Then it was time for some cold blue.

Not quite dark enough and a bit too blue with the Oxpho. Some G96 will do the trick. By itself, G96 will turn the steel black with virtually no blue. On top of the Oxpho, it'll darken but leave the hint of gun blue and gloss.

With guards done, went back to the trigger for final clean up and polish

Decided to make a new trigger pivot bushing and cross pin. In for a penny...

New trigger bushing is on the right.

The old bushing was showing its age.

This is the old cross pin. Anchors the end cap in place on the spring tube.

The new cross pin from tool steel.

Blued the ends where it'll be visible.

Some color for Mister Set-Back

Assembled the trigger to the end cap with the new bushing.

Sized a new trigger return spring. Moly grease on all the moving surfaces and put it all back together with the new cross pin.

Let's back up for a second. This is the original trigger and trigger guard.

Functional if you wear XXXL gloves.

And finally, the replacement(s) for normal fingers.

Cleaned up and refinished the old stock mounting hardware.

About 100 shots later, the set-back trigger is a home run. Trigger is now comfortable to reach and slightly smoother in pull than the original trigger blade. And I'm very pleased with the way the trigger and guard fit with the aesthetic of the little Belgian rifle.

I should probably also mention that all this work can be completely undone and swapped back to the original parts in about 10 minutes if so required.

I've no idea what's up next. That new-to-me rifle from Volvo is close to the top of the pile, but I'm not quite there yet. I came up with a quick list of airgun projects and it was pretty long. A walnut Dennis Quackenbush stock to fit and finish for my Crosman 160, Wood grips (and new trigger?) for a Gamo Center underlever pistol, a .25 Crosman barrel/breech, maybe an update on the Remington Summit in the NP2 stock, an air stripper...

Appreciate everyone checking in.

Making a Set-Back Trigger for the Belgian Hy-Score 801 Part 1

2024-09-08T18:48:00.000-07:00

With the Marksman 56-FTS finished, I dragged out the old Belgian Hy-Score 801 for the long-awaited trigger fix. This little project has been on my to-do-list for a decade. The 801 is a smaller rifle from the early 1950's. It's a step ahead in quality from the similar sized Diana 25/27 that many of us find desirable right now. There are a couple older blogs covering the 801 tear down and rebuild here. The rifle is light, comes to shoulder quickly and fires without any twang or vibration. But from the very first few shots, it was obvious that the designers had missed the mark with the trigger location--the blade sits too far forward. The shotgun shaped stock with the straight wrist begs for a trigger with more set-back.

Tom Gaylord also reviewed one of these years ago and had similar thoughts. And like Tom, I can just barely reach the trigger and make it work, but it's just not right on what is otherwise such a lovely air rifle displaying such fine craftsmanship.

Jumping right in, I separated action from lumber.

That single cross pin holds everything together.

The trigger "unit".

A quickly turned aluminum sleeve pusher

Counterbore for the trigger spring.

Traced the original trigger outline onto a piece of 4130 steel. A transfer punch marks the pivot location.

And we're off to the races--or at least the milling machine. Spotted the hole.

Through drilled.

I don't necessarily just copy hole sizes. Here, I'm using the trigger bushing/sleeve to check the hole clearance.

Notched for the sear.

Started shaping.

Deburred the hole and edges.

The sleeve pusher again.

Used it to locate off the top of the vise jaws to rough away material from the radius.

Filing the sear height.

Rather than use the original steel trigger bushing for an endless amount of test fits, I cut a piece of 5/16" aluminum rod.

No wear or tear to any of the old parts.

Looking at that original trigger position again.

Milled and drilled away material.

A small machinist jack to counter downward flex while drilling.

A few hacksaw cuts and it's starting to look like there's a trigger in there.

The Hy-Score's end cap is notched for the trigger--except the notch is about 0.025" smaller than the 0.250" steel plate I used.

Side-milled to fit.

This is where I stopped taking pics and started hand filing.

When I was tired of filing, I took material off with the bench grinder.

Not done, but good enough for a test fit to the rifle.

Location felt good, but I forgot the counterbore for the trigger spring.

Drags a little bit on the sides. Back to the files and grinder.

After a couple evenings.

How much set-back? Overlaid on the original trigger with the sear notches lined up.

Yep. Test fitting. Direct sear triggers pivot rearward when the piston rod moves backward during cocking. The piston rod notch and the notch on the trigger overlap then the trigger spring pivots the trigger forward catching the piston rod "cocking the trigger".

Installed the original trigger guard.

Then it came to a full stop. The trigger bottoms out on the inside of the guard before the rifle cocks.

Thanks for checking in. I'll have more up soon as I make a new trigger guard and do some finish work to the trigger.

Barrel Sleeve for the Marksman 56-FTS Part 4 Final

2024-08-24T08:38:00.000-07:00

Picking right up from the last blog post...

Straightened the sleeve again at work, then it was back to my basement ~~lair~~ for the rest of the milling.

Have to line up the vises for this next cut. I want a .250" radius along the top of the sleeve. Like the long flats previously milled, this is strictly for cosmetics. Trying to make something look nice for a change. OK, so the vises get lined up on the x-axis as well as to each other. This is often more difficult than it sounds. Only the fixed jaws of the vises are used for the alignment. It's a lot of back and forth until it's right. And "right" is very much relative to how accurate each piece of the puzzle is. I was able to line the two vise jaws up to just under 0.001" along roughly 14 linear inches.

Still not done indicating. As before, I got the sleeve to the exact same height at each end. I'm doing this because the groove (like those two previously cut flats) won't look even and/or straight unless this is aligned.

Most of machining is like this--all the time is spent setting things up. Used a 1/2" ball mill for the groove.

Some chatter. Probably need to sharpen the ball mill. Should've done a few things differently. Likely would've cut cleaner had I not just plunged and cut both sides at once. Offsetting each side .005" or .010" would've been smarter on my part. It'll be OK, the cut is even and doesn't run off centerline.

I though the sleeve was just a bit too plain. Since I didn't have a plan, no one will know that the drilled holes along the top were spur of the moment.

When machining, if you can make holes or slots in a straight line and evenly spaced, you'll always look like you have your act together--even when winging it.

Some M4 x 0.7mm set screws to hold the sleeve in place.

Using the same locations from the Crow Mag muzzle weight because there are matching dimples machined into the Marksman 56 barrel...

Magic marker layout.

Spotted and drilled the first hole.

Used a spring-loaded tap follower to guide the M4 tap.

The internal spring puts downward pressure against the tap as the threads are cut.

After some deburring, I did a quick test fit on the rifle, and as expected, the long unsupported rear of the sleeve would vibrate against the barrel with a metallic thunk.

Not shown, back to the vise and added a fourth set screw at the rear of the shroud as well as a M5 x 0.8mm threaded hole for the sling stud.

And two additional (unthreaded) holes between the forward mounting holes. Just for future options.

Back to the shop.

My favorite media blasting cabinet. It's usually loaded with a very fine-grained glass/sand.

Minutes later.

A little more time was spent blasting the groove to remove and blend the chatter marks.

Leaving traces of the milling marks on the sides.

Rear set screw and sling stud holes.

Didn't touch the sleeve with bare hands after the bead blasting. I think (hope) this makes the bluing easier.

First pass with an "ultra-fine" Scotch-Brite pad. Added bluing to the pad several times. This blended the color.

Then several follow-up coats--wiping it dry between each coat.

Update: About three months later, I had the opportunity to have the sleeve treated by H&M Metal Processing with their black nitride finish.

Finally, that sling stud. After a couple test fits, shortened the thread to the same length as the sleeve wall thickness.

Loctite 680 bushing retaining compound.

Set screws ground to length.

Let the bluing dry overnight, then gave it a few coats of paste wax.

And here we are.

Looks original to the rifle. The matte finish is a good match to the scope and stippling. With the sleeve, the rifle now comes in at about 10 pounds. First impression was that it shoots well offhand. Going to spend some time with it and see how it shakes out. If you follow the blog, you know I like the options and modularity from various accessories.

Not sure what's on deck, but the project list on the workbench is pretty long.

Barrel Sleeve for the Marksman 56-FTS Part 3

2024-08-20T18:07:00.000-07:00

The plan to do the milling on the barrel sleeve at work fell through. Our milling machines were set up and in the middle of operations for customers. So, Plan B, Version 1.0 it is. The milling gets done at home.

As the sleeve is 16" long, the 4" milling vise was going to need some assistance.

Dug out a second milling vise and did a rough alignment.

To mill flats on a round tube, vises don't have to be precisely aligned with the X-axis of the milling table. Each vise DOES need to be lined up with each other to hold without bending and distorting the tube.

With the vise table bolts loose, I moderately clamped the tube in each vise. Let the vises float on the mill table and essentially self-align, then clamped the vises down.

The first set up problem was to get the barrel sleeve high enough above the vise jaws to make the cuts, but low enough to clamp securely. The problem was immediately evident. My two vises don't match in jaw height. Right side vise jaws are about 1/4" higher. I propped the work up on each end with a 1-2-3 block as a workaround.

One side looks good, the other, not quite high enough.

Gage blocks make really good precision shims.

Ended up with about .200" or so (per side). As a future project, I really should make a taller set of vise jaws for the low guy.

When the high point was the same--within a few tenths--the vises were snugged up and the height double checked. Want it the same at each end of the table. This gets the work parallel to the machine even though the vises are different heights.

Four flute 3/4" end mill. First pass of about 0.030" looked pretty good. Kept track of the depth of cut on the first side with both the quill's digital readout as well as measuring wall thickness.

The tube OD is 0.875" and the ID is 0.635. That .240" difference is then divided by two leaving 0.120" of wall thickness. I'd like to end up somewhere around .040--.050" at the thinnest wall. About 0.070" off of each side.

Several passes.

"Regular" OD micrometers won't measure an accurate wall thickness on a tube. This is a ball micrometer. The fixed jaw has a radius that fits into the curved ID of the tube and contacts the lowest point.

After taking about 0.070", I was ready to flip the sleeve over and cut the second flat when I had another problem. Holding a straight edge against the flat showed the bow. The tube had warped approximately 0.011" from the milling cut. I don't want to cut side two with it out this much. Called it a night.

Took a look at my tube specifications. This DOM (Drawn Over Mandrel) tube is cold-worked. Cold (compared to Hot) working steel leaves stress layers in the steel. Milling or grinding though these layers often causes the steel to twist and warp slightly as it stress relieves. High precision parts are typically made from hot rolled or normalized steel that has been processed to remove/eliminate the stress and prevent or minimize this problem. I just remember that removing a fairly large surface area can cause the piece to move.

At work the following day, did some quick inspection.

At the hydraulic press, set on two points and lined up on the high spot.

Since I know it's exactly 0.011" out of flat, I set a 0-1" indicator under the part and offset my zero by 0.011".

With an aluminum block under the ram to protect the work, I gingerly pressed the tube. The tube has to be bent beyond the .011" as it springs back if not pressed far enough. Press, watch the indicator. Let it spring back, check the indicator. Did it move? Press a bit further this time--while you watch the indicator--then let it spring back. Rinse, repeat...

After about 5 minutes, it was within 0.0005"

Back home to the milling machine.

Side two was machined until the wall thickness was identical to the first side.

Yep, it warped again. Damn near the same amount. I'll take back to work and repeat the straightening before setting up on center for the groove.

More in a couple days. Thanks for checking in.

Barrel Sleeve for the Marksman 56-FTS Part 2

2024-08-18T17:43:00.000-07:00

I'm still stuck on terminology. This isn't really a barrel shroud is it? I'm pretty sure that shroud term usually refers to a cover that protects the user from a hot barrel. I like "sleeve" since what I'm going to make just slips over and covers.

Before I start with the actual milling of the barrel sleeve, I need to knock out a sling swivel stud that will attach to my soon to be cobbled sleeve.

Shown this process before for the IZH 61, so I'm gonna be glossing a bit.

Looks like a piece of 3/8 (0.375") drill rod. This'll do. This went into the lathe and I turned down the end to 5mm.

So I could thread it M5x.8mm

Taig Lathe tailstock die holder in action. Using this aligns the thread.

Faced off the end of the thread and added a small chamfer. This thread is going to be too long for the still to be made barrel sleeve/shroud, but I'm planning ahead for the machining four or five steps away from now. I'll need to hold the swivel stud when the opposite end gets finished.

Turned down the body of the stud.

Into a 5C work holding collet.

And a 5C square collet block

A quick positioning stop was set up so I could flip the collet block over and maintain lateral position after milling the flat on the first side.

Milled both sides to fit a QD rifle sling.

For the through hole for the sling swivel, an edge finder was used to get to centerline.

Spotted and drilled.

So, now I'm here and I made sure that a few different brands of QD rifle swivels all fit the new sling stud. Actually, I did the test fits while still set up for the drilling operation on the mill. There is/was a couple thou difference between all my different QD rifle sling swivels.

While back, I made a bunch of screw thread holders from 9/16" hex stock. Made about 8 or 10 in all the common small sized metric and SAE thread pitches so I wouldn't have to grab and damage threads with the lathe chuck.

These screw holders should've been one of my first lathe projects. They're not as accurate in concentricity as they would be if made from round stock, but they're more that good enough for most projects and the 9/16' OD makes them perfect for a wrench, vise or that three-jaw chuck.

Rough cut the end then into the lathe and turned the head to final length.

Deburred all the sharp edges and gave it a quick polish.

A bit of cold blue and--aside from the still-too-long thread--she's done.

Next up: Milling the ~~shroud~~ sleeve.

Check back, I'll have something up in a couple days.

Barrel Shroud / Sleeve for the Marksman 56-FTS Part 1

2024-08-04T20:08:00.000-07:00

Started the full-length sleeve for the Marksman 56-FTS. Didn't really get very far yet, but starting often begins long before any chips are made.

When complete, it'll look like this, but 16" long to cover the entire barrel. It's strictly cosmetic. There might be some benefit, as the additional weight should slow down movement to some degree, but I really just want to have some simple, cleanly machined lines.

As I wanted the sleeve to look like a full length version of my modified Crow Magnum muzzle brake, I had to consider how to machine the 15"+ long flats on each side as well as the groove along the top. The breech end will also need a taper, the muzzle end cut to length and beveled and finally some set screws for mounting. And a swivel stud for a rifle sling and what else did I forget? Oh yeah, where do I even start?

This is often just a mental checklist now: Will this physically fit in the machine? Do I have a way to hold it? How accurate does it need to be? What will (probably) be the most difficult step(s)? Do I need to make or buy any tooling for the project? What options to I have for each machining step? Pros and cons of each? Is this really a good idea? Am I out of my damn mind?

Purchased a two foot long piece of DOM (Drawn Over Mandrel) tubing last year from McMaster-Carr. It's 7/8" (0.875") in OD and 0.635" ID. The Marksman 56-FTS barrel is 16mm OD (0.629" ) leaving about 0.006" clearance to the tube. For reference, a sheet of paper from the printer is a pretty consistent 0.004" thick.

I opted to machine the taper at the breech end first then bring in the overall length.

Looks OK. Some fine tool marks, but the sleeve will be bead blasted in the final steps. Need to take this to length, finish the muzzle end, and polish out the OD before cutting the flats. And that's where things stalled out. I didn't want to cut and polish this thing at home. And I really didn't want to cut those long flats on my small mill.

Took it to work and got the Ok to work on it after hours.

Metal cutting bandsaw.

XXX marks the off cut. Coolant and auto feed. Sure beats my hacksaw with those Harbor Freight blades.

Cut it to 16-1/4" long.

I've shown this machine before. Its a Rand Bright cylinder polisher. Has a roller than spins and draws the tube through where it's polished by a 4" wide sanding belt. The belts are something like 90" long.

The white sheets of nylon are adjustable for tube width. I knew that a co-worker had been running some hydraulic tubes that were the same diameter the day before, so that had also factored into my desire to do this at the shop.

Ran it right through. Didn't even need to change the sanding belt. After three passes, it looked great. Probably equivalent to sanding it to 320 grit--and only took about 45 seconds for the entire job. Since the Rand Bright was already set up for the 7 /8" width, it took me longer to uncover and recover the machine with a tarp than to do the polishing.

That saw cut end needs some attention.

Over to the lathe and faced / deburred the muzzle end of the sleeve. At this point, the sleeve is still about 1/4" longer than the barrel. Again, just used the tools already in the QCTP.

Now it was time to go home and finish the length.

As expected, just a bit long.

Out to the garage and faced, beveled, then polished the muzzle end to final length.

Decided it might be smarter to polish out and remove those small machining marks from the tapered end now rather than rely on media blasting later.

Final test fit for length. Next, I'll machine the long flats on the sides. My milling machine will make the length of cut, but I'd prefer to make these long cuts on a larger, more rigid machine. And there's a face mill cutter at work that should give a better finish than the end mill I'd have to use at home.

More soon. Thanks for checking in.

Making Screw Cups for a Marksman 56-FTS.

2024-07-28T16:43:00.000-07:00

I know. I know. We haven't been posting. Some stuff came up that kinda pushed airgun tinkering to the back burner. Waaaaaaay back on that back burner. I'm gonna try to ease back in.

So, the, uh, Marksman 56-FTS. Right. It needed some screw cups and maybe a nice barrel shroud. Right there is part of my blogging conundrum. Speaking only for myself, I waffle about posting another blog about something so mundane as screw cups. Nick has shown how to make them. I've done the same. We hit the wall sometimes on new material. Nevertheless, its screw cups that I need so it's screw cups for the blog.

Removed the stock from the Marksman. That screw cup goes here. Provides a metal to metal bearing surface for the stock screws to tighten against. This is helpful because it stops the screws from slowly digging through the wood.

Before I got started, I looked at some of the other existing hardware on the rifle. The cheek piece fasteners are blued steel. I'll follow suit and go the same route so it looks like this was actually planned in advance and not designed by the party committee.

Rather than try to measure directly, I grabbed some transfer punches. The graduated sizes are pretty handy for a quick reference.

Best fit was a 13/32" (decimal equivalent 0.406")

Found a scrap of .500 diameter 12L14 steel in the scrap pile.

Cut off an even smaller piece.

Face one end.

Turned down to just over 0.406'

0.408" and a couple tenths should be close enough. I'm looking for a snug fit.

Some M5 socket head cap screws.

Through drilled

Testing for clearance.

Drilling a counterbore to recess the head of the fastener.

To produce a flat bottom in the hole, I'll finish it with an end mill. Seems like I never have the diameter I want...

Just took out the drill point and made a flat bottom in the counterbore.

Test Test.

See how the shank flares slightly just below the head? If the through hole is too close to the screw diameter, this can hang up and not let the base of the head seat flush.

Rather than making the through hole larger, chamfering the top of the through hole will fix it.

Cut off, flipped and faced to an unshown predetermined length.

Screw cup #1.

Now for the second. Since I've made screw cups for various air rifles before, I know that they're not necessarily identical in diameter or depth.

Screw cup number two ended up about .010" larger in diameter to best fit the factory counterbores.

Test x 3

Blue time.

And finally, installation and the glamour shots.

Just what I wanted. Looks like they were there all along.

Next up, I'd really like a full length shroud. Like it to look like the muzzle weight, but run the full 16" barrel length. The metal is on the work bench, but I'm unsure if I can do the machining here at home or if I'll need a larger mill. More soon.

Side notes of note:

I met up with renowned air gunner and just generally good guy, "Volvo", the other day. I still re-read his blog and wish I had the style and quick wit he wrote with.

https://namericanairguns.blogspot.com/

Ray, thanks for sending me an email checking in with me. It was good to hear from you

Early Marksman Mod 56-FTS / Beeman R11 / Weihrauch 98 History

2023-10-29T13:58:00.007-07:00

Took a vacation last week. Cabin in the Smoky Mountains near Waynesville, NC. Between the hiking and raindrops, we found some time to do a little bit of air rifle shooting. Brought a rifle along that probably hasn't seen any screen time on this blog. It's an old Marksman Mod 56-FTS. The FTS stands for Field Target Special. The rifle was made in Germany by Weihrauch and it dates back to the late 1980's. Marksman also sold the similar Mod 58S geared toward silhouette shooting with a shorter barrel, full length barrel weight and non-adjustable stock.

The Marksman branded Weihrauchs always bring back good memories of my early airgunning. My first air rifle experience was a borrowed Marksman Mod 70 (a HW85) and that quality and accuracy made a huge impression.

The 80's were a long time ago and oddly enough, Marksman was selling this Model 56-FTS several years before Beeman started selling the almost identical R11 (HW98).

Looking through old issues of American Airgunner, I found a full-page ad inside the front cover for Marksman Mod 56-FTS in the July/August/September 1989 issue. Vol 4, No. 3. That puts the Marksman on the market about four years before the Beeman R11/HW98 hit the states.

The Beeman R11 --what we know today as the earliest version HW98-- appeared in the Beeman Precision Airgun Guide Edition #18 in 1993. Makes sense -- since SR Industries took over control of Beeman in April of 1993. The first version Beeman R11 blended the Marksman Mod 58S action --short barrel and full length barrel weight/sleeve--with the Mod 56's adjustable stock.

Here's a pic of the 56-FTS.

Seems like the rifle should've been much more popular. The stock is ambidextrous and the adjustability makes it easy to get a comfortable position.

Several years ago we overhauled FrankB's internally similar Marksman Mod 70 here.

Bought this rifle new from the now long gone Precision Airgun store in Maple Heights, OH. --And a trigger shoe and some sling mounts apparently. It was tuned before I started writing this blog with Nick. I may revisit the teardown as I don't recall any of the tune specifics. I don't know if I made a new spring guide, a top hat, rotation washers...

Side note: This is one of the airguns that Weihrauch made right after they acquired BSF (Bayerische Sportwaffenfabrik). I have no idea what Weihrauch got out of this deal. Machines? Workers? I always read about the guns being made "on BSF tooling" or something equally vague. If you look at the BSF offerings right before the acquisition, about the only thing carried over was the separate scope rail attachment. Oh yeah, some of the rifles (like the Marksman Mod. 70) got rear BSF sights. Stocks, barrels, and triggers all look like HW items. There WAS however a retooled trigger housing/carrier --from HW--that allowed them to use both their Perfekt and Rekord triggers on compression tubes that did not have threaded endcaps. The trigger components themselves were essentially unchanged.

So, I wonder if Weihrauch had originally intended to develop a separate line of air rifles and market them under the BSF name, but the Marksman deal came along and that name was chosen instead? Makes more sense to me than just "on BSF tooling".

Anyway, this is a HW Rekord trigger...

...with a very different safety. This one is on the right side of the gun (there are left side versions out there, too) The lever is fairly convenient. It automatically goes to "SAFE" when cocked, but unlike the standard HW button safety, this can be returned to "SAFE" after being moved to the "FIRE" position without re-cocking the barrel. However, due to a trigger blocking safety that engages when the rifle is broken open for cocking, the Marksmen rifles cannot be UN-COCKED.

Here's that BFS designed 11mm dovetail rail attached to the rear of the compression tube for scope mounting. I wish HW would've redesigned this rail and made it picatinny.

The 56/58 rifles had no provision at all for iron sights. Looks like I used some Sportsmatch scope rings along with a Leapers/UTG 4-16 scope.

Cheek piece is adjustable for height. The buttpad adjusts for height and rotation angle.

One of the only HW stocks I can think of that was stippled rather than checkered.

I replaced the forward stock screws with hex heads, but didn't make any screw cups at the time.

Originally, the Mod 56 was fitted with what we used to refer to as the "Crow Magnum Muzzle Brake"--or the 3-screw Beeman muzzle brake or something like that. Really, it's just a muzzle weight.

A couple years ago, I milled flats on the sides of my muzzle weight...

...and cut a radius down the top side with a ball shaped endmill before bead blasting and bluing. For, um, panache. If air rifles can have panache.

Those three screws.

I really like the lines of this modified barrel sleeve. Wanna look in the metal stockpile for a drawn over mandrel (DOM) tube that fits over the barrel and mill a full barrel length sleeve with the same profile.

And make some forend screw cups. Whatever I end up doing, it'll be a good excuse to spend some quality time with a Weihrauch--and that's always time well spent.

More soon.

Where Are They Now? The BAM B26-2

2023-09-10T07:13:00.004-07:00

Something a bit different today--a quick revisit. Been at least six years now since the .22 cal BAM B26-2 has seen the light of this blog. Thought I'd follow up with how it's been going. Forgive me as I'm not finding all the right words to express myself this morning, but I'm plugging along anyway. If you've followed this blog, you'll recognize that I've long been fascinated by the mechanicals and the ergonomics of dedicated target-type guns. The precision accuracy coupled with the adjustability of the stocks and grips made an impression. There's a uniqueness and almost a science fiction aspect to some of the equipment. All purpose driven to improve the shooter's results. My mechanical aptitude is attracted to that uniqueness, the engineering and manufacturing. And since I'm interested in experiencing these features--especially in a price range I can afford--I attempt to incorporate some of them into my various field/sporter airgun projects.

Originally purchased this (in person!) at a Pyramyd Air open house. Way back in 2008, this rifle for some reason was on my hit list. It was a lot of things. Wanted to try a thumbhole stock, it was available in .22 cal, liked the overall design, wanted to see how the quality of the BAM air rifles had progressed...

Spent some time working out the accuracy and ergonomic issues the rifle presented. Certainly got some blog fodder out of it--maybe 12 or 13 posts worth. This rifle (and an evil Remington Summit) taught me quite a bit about how important positive, consistent barrel lock up is--and how difficult it can be to achieve. The 26-2 also really drove home the point about ergonomics and fit. The original high cheek piece made it impossible to get a comfortable position behind the scope. Even with high rings and a riser adapter, I was smashing my face into the stock to see through the scope. Amazingly, after lowering the absurdly high comb, this is now one of my favorite rifles to shoot offhand. That adjustable palm shelf and buttpad allow the rifle come to point immediately because the hold is so consistently repeatable.

The padauk wood has darkened and mellowed a bit from the bright red when it was freshly cut. This particular feature was inspired by the Anschutz 1913 Supermatch rifle.

The quick set Devcon epoxy is still holding the rubber pad to the aluminum plate without any gaps.

The barrel sleeve has been refinished at least twice over the last twelve(?) years. It's next to impossible to keep a cold blue finish on gun parts that are handled as much as a break barrel. Got a blued, bead-blasted finish at the moment. If (when) it needs another refinish, I'm going to try my hand at rust blueing as I expect it to be much more durable.

Update: I had the sleeve treated with black nitride by H&M Metal Processing in November of 2024.

Made a replacement pivot pin for the cocking linkage at some point. Nearly identical to the one we blogged for the .25 cal R1.

Seems like the only real change over the years was a scope upgrade. Originally, I believe the B26-2 was wearing a fixed 4X power Leapers Bug Buster. Switched to the 3-9 variable power Bug Buster a few years ago backed up by a separate scope stop.

The scope eye relief combined with the short mounting area for the rings wouldn't allow the stop pin in the scope ring to line up with the hole in the receiver. The separate scope stop solved the problem.

There were quite a few modifications made over the years--from the stock surgery to the chisel detent barrel latch. The 26-2 slowly morphed into a very fine shooter. The scope relative to the bore line is still high, but it's now a very comfortable heads up position rather than a smooshed face position. I look back at the original comb height and marvel that BAM designed a stock solely for a guy like Herman Munster. I should put the rifle across the chronograph again and see where the velocity is compared to the original tune over a decade ago.

Maybe later this week just for fun...