To produce a small scale, high pressure cannon to rival the pengun series.
The twist?
Supply similar power, but with a 5+ round capacity!
Well after a lot of tinkering, blood, sweat and tears it's complete!
Construction is stainless steel, brass and epoxy with small amounts of plastic, spring steel and aluminum. On this scale, the most feasible way to give five consecutive shots was to use a hammer valve. And what better pre-made, low flow hammer valve that is cheap and available anywhere than the schrader? That said, it needs extensive modification..
The first adaption was to use a saw to cut down the top part of the valve, just above where the inside threads start then to smooth it off. At this point it's worth mentioning the variety of core I used. It's the longer type that has a long exterior spring. Easy to cut down, modify whatever..I completely cut it off. High pressure air easily closes the port.
Last of all, the part which is hardest to explain without photos.. the schrader was made to port directly up, rather than waste the tiny volume of air re-cocking the hammer.
The hammer is a stainless steel shaft, with a smooth plastic outer to reduce friction. The spring is simply a pen spring..nothing more to it. It's fairly soft, allowing for multiple shots.
On to the first test. The compressor was turned on (shock pump is broken, should get a new one..) and the chamber was filled to 70 psi and left for 20 minutes with not even 1 psi of leakage. Then the chamber was pressurized to 100 psi and the hammer actuated. It gave 6-7 full power shots then the power began to ebb away, eventually the pressure could not close the port and it leaked out slowly.
There's no barrel on it yet as I still need to make the persplex elbow (gah, why don't they make elbows in 3mm?)
If all goes well it will be encased in an epoxy stock then used with my (soon to get a new one-broken) shock pump for 400 psi shots.
As JSR would say, watch this space.
Mechanism..Left-fill valve, right- hammer re-cocking mechanism. The brass bushing in the middle houses the modified schrader and porting.
Mechanism and barrel, with Clide's cardapult for scale.
Future upgrades will include a trigger/sear, full automatic, a magazine, sights, a stock..the works.
Edit: gah..only just realized the pictures aren't to great. I'll do the barrel then shoot some with the canon.
Edit2: I just had a thought, flip the barrel towards the hammer end and use the hammer lever similar to a pump action or keep a traditional trigger/sear setup and face the barrel towards the fill valve?
how did you plan on achieving full auto? And why not a piston grip instead of a stock?
