Most of the projects I do in my machine shop are just for me, or maybe for Michelle. But once in a while I get a paying job. A few years ago a friend asked me to make a highly customized air rifle. I recently found some photos of the finished product, so I thought I would share.

Good Bones

We started with a Crosman model 2289 Backpacker. The exact rifle isn’t made anymore, but it’s very similar to the current Crosman Drifter. It’s a multi-pump pneumatic rifle with a detachable stock. You can use it as either a rifle or as a pistol, and the removable stock lets you easily fit it inside a backpack (hence the name). The concept is that it would be a handy little rifle for a survival kit. I’m not sure how useful it would really be, but it’s a fun idea.

The stock rifle has a 15″ barrel in .22 caliber. It comes with some basic but adequate iron sights, but there’s no way to mount a scope. The trigger pull feels rough and unpredictable. A lot of the parts are plastic, including the breech, which isn’t conducive to really fine accuracy. In short, it’s just as cheap as its price would indicate.

On the other hand, it has good bones. The pump system that powers the rifle is fairly efficient. The trigger can be readily tuned to be fairly crisp and predictable. And, best of all, there are lots of custom parts available.

On the right is a completely stock rifle. On the left is the customized version.

A Long Punch List

The biggest change my friend wanted was to convert the rifle from .22 caliber to .25. That entailed changing the barrel, the breech, and the bolt. All of those parts are available to purchase, so that was pretty straightforward.

But those changes spawned other changes. The new barrel was bigger around than the stock one, so we needed a new barrel band. Unfortunately, nobody sells those, so I had to design and make my own.

The brass thing on the left is the barrel band. It’s actually in three parts: There’s a piece that goes into the pump tube, the barrel band that supports the barrel, and a clamping part that joins the other two. On the right you can see the aftermarket trigger and safety.

The new breech would accommodate a scope mount, which was good. But it came without the plug that covers the back end (behind the bolt), so I had to design and make that too.

The trigger parts that my friend bought were brass, so we made everything else from brass to match.

My friend wanted me to do some work to clean up the trigger pull, and install some aftermarket parts to help improve it further, and add some nice cosmetic touches.

Finally, the muzzle of the barrel was threaded, and he wanted some sort of cap that would screw onto the threads and look nicer.

The hard part was getting the small end of the taper to match the diameter of the barrel.

Sorry, No Build Pictures!

I built this a few years ago, before we had a blog, so I didn’t take any pictures of the build in progress. It’s a pity, of course, but it probably saved me a lot of time.

The Result

The beauty shot!

The rifle looks great, and it’s quite accurate. The trigger has a very crisp break, which helps the shooter realize the full potential of the rifle. But the low velocity limits the range quite a bit, which was a little disappointing.

The power, though, was lacking. It produced about 425 feet per second (fps) velocity with 15 pumps. In .22 caliber the rifle would produce about 550 fps with ten pumps. But .25 caliber pellets weigh about twice as much as .22 pellets, and I think the pump system on this rifle just doesn’t have enough mojo to move the bigger pellets very quickly. That limits the effective range of the rifle.

Still, it’s a one of a kind piece, custom designed for the owner, and he takes a lot of pride in it. So I’m counting it as a success.