sprung ball valve hand cannon

[spudamine]

This is a little something I felt like putting together as my main project at the moment is grinding me down a bit. This is a spare parts cannon with little or no planning or optimisation. I wanted to use the handle and custom T piece from another project which never got finished and I've never made a ball valve cannon before, plus adding a captive piston sounded fun as well, here she is:


there's a sneaky pressure gauge built into the base of the handle, recessed of course so as not to be damaged whilst pistol whipping the undead

The cannon originally had a captive piston (copied from one of btb's creations) but despite functioning correctly it wasn't noticably quieter, I guess the sound of the piston hitting the fitting at the end of the barrel was just as loud as the expanding gas without it so I removed it and tried some saboted darts instead, here are the bolts for the cative piston, unfortunately I forgot to take a picture before firing:

and here are the darts with sabots and pushers:

And what they did to an old frying pan, fired at about 400psi:


here's a video with some more detail and, of course, more damage.
[youtube][/youtube]

[farmerboy32]

this is really awesome dude! i really like your clean trigger setup! keep the good work!

[Gun Freak]

That's a wicked little pistol. Captive bolt sounds cool too, you don't hear about those too much. Nice work!

[Gaderelguitarist]

Beautiful pistol. It definitely packs a punch based on the result of mixing it with a frying pan.

Spring operated ball valves have a sort of "flintlock" appeal. Combine the aesthetics of BTB's Old Shatterhand with your pistol and I'd have to give you a 10 out of 5.

[jackssmirkingrevenge]

Brilliant!

For a "spare parts" launcher it's miles ahead of what some people here achieve in their lifetime

Some details of your captive piston setup would be appreciated, perhaps we can figure out why it didn't work according to plan.

recessed of course so as not to be damaged whilst pistol whipping the undead

I knew it!

[daniel0663]

Awesome ! looks clean for a spring loaded air gun.
Loving the gauge.... oh ! and the laser....
and the custom grip. I love everything about it...

best gun I've seen in a while ..

[Doctore]

Nice airgun!!!
Best spring airgun I have seen so far.

[saefroch]

Love the captive sabot idea. And the damage to the frying pan is rather terrifying but... is that frying pan copper?

[spudamine]

Some details of your captive piston setup would be appreciated, perhaps we can figure out why it didn't work according to plan.

Well it's fairly simple really, aluminium piston in the barrel with a floating o-ring seal (a spare from my 2-stage pump). this is held in by a solder fitting on the end of the barrel (only shown in the video not the pictures) which is reinforced with a few bolts. It was definitely trapping the muzzle blast as there was a slow hiss after firing as the gun slowly emptied pressure, but it still sounded quite loud. I should probably have used a lighter piston, I think BTB used a rubber one, even though mine was quite lightweight it was still hitting the 'end stop' with enough force to completely mash up the spring after a few shots and also deform the piston enough that it had to be reground to slide in the barrel smoothly. Accuracy of the bolts was also quite woeful, probably due to a fairly poor effort at a whisker biscuit on the end of the barrel, so I got rid of it and used darts instead.

Love the captive sabot idea. And the damage to the frying pan is rather terrifying but... is that frying pan copper?

nah, just aluminium, I wouldn't waste a copper pan
That's actually the second one I've shot up in my spudding career, they just seem to annoy me.

[jackssmirkingrevenge]

Have you considered an air cushion?

[Gun Freak]

Those all seem impractical and/or very difficult to make 8)

[Technician1002]

Aluminum frying pans are soft. A woman with bare hands can roll one up to save space.
[youtube][/youtube]

How well does it perform with a stainless steel pan or cast iron?

[Sch120PVC]

Great gun mate.......i checked out your other spudgunning videos on youtube and you seem to me following spudgunning more than just a hobby! all your designs are beautifully machined! Keep it up, and you really should be proud of this little beast!

[spudamine]

Have you considered an air cushion?

that should be quieter, the top one would look quite cool firing and wouldn't waste any barrel length, would be a sod to make though.

How well does it perform with a stainless steel pan or cast iron?

Tec, one of my key strategies for not getting a bolt in my head is to match a hard projectile with a softer target or vice versa so I think I will keep my cast iron pans where they belong for now thankyou

Great gun mate.......i checked out your other spudgunning videos on youtube and you seem to me following spudgunning more than just a hobby! all your designs are beautifully machined! Keep it up, and you really should be proud of this little beast!

Thankyou, not strictly machined but a lot can be achieved with a drill press and a good saw. sadly my pillar drill is on it's last legs after about 5 years of constant abuse being used as a crude lathe, mill and sander. Maybe I should replace it with a mill...

[Brian the brain]

I think BTB used a rubber one

yep...

With a bolt through the center for the arrow to hang onto and stay centered.
Some thick rubber hose would do the trick.

both lightweight and silent.
And it eliminates the need for a bumper..

Thanks for trying it out though!

Very clean build!
If you could flip the action on that BV it would be more like cocking a flintlock..

If that's your thing...