updated! portabal gravity feed cannon questions

[Mark256]

this is my design plan for a semi automatic or burst of two or three 6mm plastic BBs

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it will be my first PVC Air Soft gun.
Does this look like a good Idea, because I want a semi-auto without mechanical parts (springs, pistons, etc.)

what would be the disadvantages and the advantages?

How many shots do you think I could get if I shot individually?

would it be practical to play air-soft with it?

do You like the gun and would you build it if you wanted a portable semi-auto gun?

how much power and how far do you think it would have by your experience?


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Okay, here is my updated version I think it will shoot many more times because the second chamber only allows it to shoot a small amount of air at once.
I just have to hit the valve closer to the tank then hit the other valve to release the BB.

And much more powerful due to the new breach loading method.

how do you think it will preform?

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[TwitchTheAussie]

Well first disadvantage is the image didint work and second I see no probs with a gravity fed cannon.

[judgment_arms]

There’s a link at the bottom of my signature entitled “Spudgun Safety Rules”, click it read the rules, learn them, and memorize them. They’ll answer a few of your questions.

And welcome to the forums!

[hi]

other than the fact that the bbs will roll down the barrel when its pointed down and the fact that you will have about 2 seconds worth of air, yes, it woud work.

[keep_it_real]

You're going to need lightning fast fingers to only shoot one at a time. A lot of air is going to go into the hopper reducing the speed. This will also shoot the bbs up and it could take a while for them to fall back into the barrel. If I were you I would make a small barrel sealer with a slide valve for a trigger. This will take care of the semi auto part. I know you don't want to make any pistons but I thats the best I can think of at the moment. Just make a hot glue piston and find some rubber. For the hopper ummmm. you could make some kind of blow forward bolt (search for clide's semi auto) but that could be hard. If you don't want to build a bolt, make a clip instead of a hopper so theres less dead space.

[lukemc]

i made something similar and it works fine




i hooked up a blow gun from an air compresser and it is almost imposible to shoot 1 in a very short burst it shoots the whole "clip"

also you need a good way to feed the bbs down it hard to do without jamming

the way to stop bbs from falling out of the barrel i drilld a hole where thy feed a tiny bit down so the bbs pocket into it and dont move

[jackssmirkingrevenge]

have a look here, you'll get a more efficient design.