Semi auto PCP pistol

[JPSAXNC]

I have an idea for a semi auto pistol. I have a grip frame from a Benji 422 it has a semi auto trigger and sear. I could attach it to a tube. The firing valve and hammer would be a copy of the Crosman 600 valve and hammer. The 600 valve and hammer have a big advantage because the hammer is sealed to a projection on the back of the valve. requiring only a tiny amount of air to cycle the hammer. The hammer and bolt would be connected together with a pin so the hammer would carry the bolt forward and back. The disadvantage is that the pistol would be long because I would need 7" of reservoir from the back of the fill valve to the front of the firing valve. On the plus side, the barrel would be long. Also on the plus side the overall profile would be fairly low, like a 2240 using a jet magazine. The overall length would be about 13". It's all in my head right now but I can see a good possibility it would work. I'm going to order a tube and 7075 aluminum for the valves.

[JPSAXNC]

I ordered the materials we'll see how it goes.

[sb327]

I’m not familiar with the parts exactly you are using but it sounds interesting and I’ll be watching.

Dave

[JPSAXNC]

The Benjamin 422 is a co2 semi auto pellet pistol, a clever design with a sketchy magazine and feed system. The Crosman 600 is also a semi auto co2 pellet pistol, more mechanically complex than the Benjamin. I think both of these guns could have benefited from the spring loaded rotary magazines we have today. That's what got me thinking about building one.

[JPSAXNC]

I got my materials but I'm recovering from pneumonia. It's to cold for me to go out to the shop for now.

[JPSAXNC]

I made a sketch of where the parts will go it's looking good, almost a lego gun. This coming week it's supposed to be warmer, I'll cut some metal.

[rsterne]

Looking forward to seeing it.... Your projects are always interesting....

Bob

[Habanero69er]

Following.

[JPSAXNC]

I have started work on the valve and tube. I'll start the hammer and will finish polishing the tube ID. today. So this gun is a combination of the Jet hammer and bolt probe stroke lengths, it will use a Jet magazine. The Crosman 600 style valve will use the Jet style poppet and seat, because it's very easy to open, and the Benjamin 422 grip frame. It's a bit of a challenge to get every thing lined up on paper, so I'm making all of the parts to get a better idea of how they will fit together.