Crosman 105 Disassembly, Part 1

I picked up this Crosman model 105 a while back on Gunbroker. It’s missing the grips as well as a few small parts but is otherwise in good condition. The 105 is the .177 cal model, the 106 is the .22 cal. model of this pneumatic pistol. There’s a general post about the 105/106 on the Pyramyd Air blog.

The odd thing is that the pistol has no markings at all. I’m wondering if it’s a particularly early model or if it’s what we now call a “second”.

Of course I love the loop pump lever. These are often found in a deformed state and later models changed the design so that the smaller open section is closed.

No markings…

Let’s get started/ One screw.

It looks like it’s not original?

The other screw wouldn’t unscrew.

So I removed the barrel band/front sight.

The dowel pin keeps it aligned, which is a nice feature.

Ahh, it’s not a screw, but a screw headed pin.

Removed.

Then it’s a matter of removing the front pivot plug.

A simple milled piece.

And the piston assembly is pulled out.

Linkage pin removed.

There’s a setscrew which locks the piston adjustment.

Pump cup assembly removed.

I used a Taig 3 jaw chuck with soft jaws to get a grip on the pump cup assembly and unscrewed it.

Fairly typical period pump assembly parts. More to come…

Walther LG55 Final

Not much left to report. With the leather piston seal well oiled and the anti-beartrap fixed, I went to the spare mainspring box. Ended up trying a few different springs but didn't see any difference at the chrony. So I reinstalled the original spring.

Original spring is on top. Rebuild was pretty much a reversal of the first post. The spring got a razor thin coat of copper anti-seize. Painted it on the coils with a flux brush to get complete coverage. Then added two very thin hardened steel rotation washers to the base of the spring guide. Cocking linkage and the outside of the piston were burnished with moly. Went really light on everything in the hope that the velocity would climb into an acceptable realm. The gun was assembled and test fired about fifty times to burn off the excess lube in the compression chamber, then the barrel was cleaned and the gun set aside.

The barrel weight was missing the set screw at the breech end of things. The hole was also stripped. Looks like it was initially an M5 x .8mm thread.

I opened it up by running an M6 x 1.0mm tap through the hole.

Don't forget the cutting oil.

An M6 set screw is way too long.

Cut it down and slotted with a saw.

A bit of cold blue...

And it's pretty well blended in.

Went through my pile of inserts looking for a suitable annular element. A Feinwerkbau--or maybe it's a Weihrauch--4mm insert fit the bill. Much better for shooting at 10 meter targets.

Here is the high end of the chrony's tale. It's more than a few feet faster than I expected and very consistent. Gave the rifle back to Guy Sunday morning. He looked pretty happy.

A.B.T. Shooting Gallery Rifle, Final Notes

Finally found some time to put the A.B.T. back together…

This needed some fixing.

My precision drawing.

Surgery.

An attempt at precision.

A walnut block.

JB Weld. Why? Because I was out of clear epoxy and didn’t have time to go to the hardware store. It’s not going to be visible.

Clamped up. I let it cure for a day.

I roughed out the block with the mill.

Almost done.

I left it oversize so I could fit it after I reassembled the rifle.

Another shot of the receiver.

Sear.

Fitting…there was a bunch of chiseling and rasping.

Now to drill the hole for the bushing. I left those steel plates because they look cool. This was a gun that was used by thousands of people.

Fitted.

The wood broke out as I was drilling – from this side…some days I can’t win. But again, nobody will see it. Except you guys.

Some air fittings.

A long drill bit, paper and glue.

Makes a tube.

I decided to try regular .170” BBs first.

In the loading trough.

Plink.

Airgun dork.

This is at 15’

I then tried .177 lead balls. I loaded them directly in the trough without a tube. Which worked fine, FYI.

And 3/16” ball bearings, which are I believe the ammunition the rifle is supposed to use. These were all at 80psi from my crappy compressor – I wonder if more pressure was warranted. I’ll bring it over a friend’s shop sometime and see how it does with more air pressure.

Making a tube for 3/16 ball bearings.

Exciting as watching glue dry.

Glue drying…So that's pretty much it. A nice piece of Carnival history. Now I just need to find a complete shooting gallery and I can have a nice summer job.