precharged round gun (still redesigning)

[pizlo]

As I hinted in one of my previos post I think I have found a solution to the precharged ammo problem. As has been speculated about before I plan to use c02 cartridges. I had the idea in school when the other (lower grade) technology class was testing they're c02 dragsters. there wooden cars that have an 8 gram specialty c02 cartridge in the back. these things go with some force, so I fugured they would be plenty to poser themselves. The special supplier sells the for 60 cents a peice, but I'm friends with the tech teacher and I might be able to get a better price.
Anyways the first thing I thought was a hammer to burst the seal, but I realized that that would never seal the back. So I used the basics of homeade nerfguns, and an idea I got from the 100% seal piston. heres a diagram.

The barrel will have to be some pipe with 5/8 ID. The blue is neoprene. The red is a clothespin used to as part of the exaggerated cache mechanism.

I hope you all understand the cache mechanism. At first I thought I could make it primed by a bolt, and breach loaded, with the same bolt, but because of pipe sizes in the barrel and plunger tube theres no way a pipe top from the barrel could slide back. the simplest way to prime it would be to extend the plunger out of the pipe, put a ring on it and pul it back, but this protrusion can get in the way, to I have a plan for a bolt that brings it back, then the bolt slides back forward. Pretty much I would have a pvc rod with a T oh the end that went over the plunger, then I would add a washer near the cache for it to push against.
The neoprene is there to seal the back of the barrel, And I don't think I'll have any trouble keeping the seal, or puncturing the c02 with the Uber spring I have in mind.
so thoughts concerns Ideas to improve? I'll be updating this post with changes and problems solves.

[jackssmirkingrevenge]

If you're luck, the air pressure might recock it for you, then with a bit of tinkering it could be made a semi-auto.

[pizlo]

Hmm cross your fingers!
So does anyone see any problems or improvements I could make?
I would really like this thing to work

[iknowmy3tables]

well trying to get it to burst faster, the CO2 apparently doesn't spill out all at once if you've seen the dragsters move, you ought to make a way for pressure to accumulate first

[pizlo]

hhm, an O-ring might work, but I doubt I could get it right. maybe just a longer barrel?

[jackssmirkingrevenge]

Maybe a tight fitting bit of hose or a spring loaded detent, anything that will delay projectile movement until the pressure can build up a little will give you a definite advantage, and also make it easier for the bolt to pierce the cartridge. Naturally a longer barrel also helps, as long as you can manage.

[pizlo]

Yay something to think about tomorrow in school. This whole thing is turning out to be more complicated then I originally planned. Still, theres a chance.