Automatic Fire

Cannons powered by pneumatic pressure (compressed gas) using a valve or other release.
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judgment_arms
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I’ve got an old ¼” slide valve that when you pull back the sleeve it cut’s off the flow and opens up the other end, wonder if that’ll work?
If I fill through the sprinkler valve, how fast will my chamber fill, would it be any slower than if I used a small piston valve?

EDIT:
I just tried to fill through the sprinkler valve and nothing happened, I hooked the quick-connect nipple right up to the elbow I got sticking out of my modded sprinkler and the chamber wouldn’t fill. Is there some modification I need to do to the valve to make it work or what?

And yes, I’ve used this sprinkler before with a blow-gun and it works fine, other than sounding like and angry wookie…
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jackssmirkingrevenge
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Hmm... I think it depends on the model whether you can fill through the pilot area or not. As to what would fill quicker, it's all a matter of filling and equalisation flow, pilot and chamber volumes etc. so you're either in for some pretty tough calculations or many happy hours of trial and error :)
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If you want to fill a sprinkler quickly through the pilot, simply tee off the input and run a line to the chamber with a check valve in it.
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judgment_arms
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I’m thinking I might try for a piston valve, a small one, to save on space. It couldn’t hurt, right?
As for figuring out pilot and chamber volumes, I’ll do a little of both, some basic math, and lots of trial and hopefully not too much error…
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iknowmy3tables
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yeah my gun doesn't fill very fast but what i did to increase flow is cut an angled flap to create a swinging check valve flap, I believe a qev is the best

and for a nice sleeve gun you need a valve with slow.. back flow or what ever, or a check valve fill will be necessary for a rapid fire gun
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jackssmirkingrevenge
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one thing that would help is to somehow fit a check valve to your equalistation hole - this will help you fill the chamber quickly without compromising piston performance.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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the best thing would be to tap a hole for a check valve in the top and connect a tube to the chamber and check valve, but that cost money :D
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If you wan to make the tommy gun then I suggest using square tubing. Then you could have a square piston valve. there would be half of a 45 degree tube at the back which would go into your stock where you could attach co2 or a compressor hose. Then you could an actual magazine for your casings in the front. That would look just like a tommy gun but I still don't see how you could get the bolt and the piston back without having some of the gas push it back or a motor. The barrel could also be a half inch barrel. The casing could be 3/8 copper couplers. 40 caliber paintballs fit well the couplers without much wadding. 40 caliber paintballs can be found on Rap4.com or ebay.com. I'll try to draw you a picutre to explain what I mean.
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judgment_arms
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Us sniper, although a Thompson would be nice, it’s not what I’m gunning for, I merely mentioned it to stress the “out of WWII” point.
I’m look more towards the automatic rifle/LMG/SAW look.
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iknowmy3tables
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really which country would this gun's design originate from US, Germany..., if you choose Britain you could get the ghetto award :D
us sniper
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I am not sure if you mentioned this, but where is your air source. Is it on the gun, a compressor, or in a back pack? Also, is there any valve that you are trying to use on the guns or any one that makes it the most life like?

Here is a good site for paintball guns. This may or may not be what you are looking for but most of the guns could be modified to use casings by making a longer bolt. http://www.ultratwistedpaintball.biz/pa ... TIONS.html

I am also building a semi automatic gun like you. Mine is going to look like a m16 instead. I am using the 3/8 couplers with the 40 caliber paintballs. it allows you to fit more rounds in the magazine.
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judgment_arms
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Iknowmy3tables, for this gun I’m shooting for U.S.
I’ve got an idea for a belt-fed MG42 and I’ve always thought a Lewis gun would be cool.
But a STEN would be fun, not to mention simple!

For Us sniper’s question, for know air compressor, latter on I’ll put a bulk fill on it, provided it works.
And I’m only using paintballs because they’re safe, people get will most likely get scared if I were to shoot .735dia lead balls, or 12ga rifled slugs.
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iknowmy3tables
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And I’m only using paintballs because they’re safe, people get will most likely get scared if I were to shoot .735dia lead balls, or 12ga rifled slugs.

boring, are your parents the one's you might scare,

belt fed is quite a challenge so mg42 is a bit hard, lewis sound nice

and put me on as a 3rd for a person planning an automatic cartridge gun, I'll be trying belt fed ejecting 1.5" shells in the not so near future
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judgment_arms
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Scare my parents? Heck no! they know I’m not dumb enough to do something dumb, I’d use a sufficient back-stop.
No, a ton of houses popped up behind our house and I don’t want one of our new neighbors calling the cops saying, “he’s got a machine gun!!!”…

Funny you should mention a 1.50cal belt feed, I’ve bean working on a 1.50cal hoper fed auto-cannon for a paintball tank armament.
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iknowmy3tables
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wonderful may be we could help each other, i understand the whole thing about getting reported for something legal, I was thinking that once i got my canon built maybe i could attract some attention and get invited to sienrio games
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