Breach Loaded Pneumatic Rifle

[Potato Demon]

I was at the hardware store a few days ago and I thought “Why not make my 9th spud gun?”. Do I did. It managed to stick a blowgun dart in my garage door from around 10 feet at 100 psi and it shot through 3 or 4 layers of cardboard prior to doing that. The thing that makes it special (for me, at least) is, the barrel slides forward and I can load stuff in like that instead. I haven’t done a range test but I bet it would go 50 to 100 metres. The spacer is a piece of wood (the writing says spacer so I wouldn’t accidentally throw it out) and a bent 35 cent bracket.

[farcticox1]

PVC makes me nervous now, it's not rated for gas pressure, I have used it but wouldn't again.

[Labtecpower]

Good start! reminds me of my own first cannon

You can very easily enhance the power of a ball valve cannon by opening the valve with a spring loaded mechanism instead of by hand, it will open the valve much faster than you can do yourself. Now the projectile leaves the barrel before the valve is even half way open.

I have successfully used the following mechanism on a few of my guns; the ball valve actuator is mounted on the shaft of the ball valve and is kept under tension by rubber bands or equivalent, and held in place by the trigger. Should speak for itself, it's a very simple mechanism to build Keep on tweaking and making improvements, it's the best part of this hobby.

[farcticox1]

Or springs

And if you drill a hole in the ball valve you can load straight into it, can cause it to leak a bit though.

[jackssmirkingrevenge]

PVC makes me nervous now, it's not rated for gas pressure, I have used it but wouldn't again.

In practice it's fine if you don't abuse it.

+1 for spring-loading your ball valve for meaningful power and a modicum of accuracy

[Potato Demon]

I’ll try both mechanisms, I’ll probably make a second one like this out of steel pipe so I can use one mech on each.

[farcticox1]

This one is pretty simple, and it uses a bike pump

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