advice on paint grenade launcher?

[conkfa47]

First off, I just wanted to say hello everybody! im new to these forums and building spud guns in general, so im looking forward to learning a thing or two . I was just wondering if someone could maybe help point me in the right direction for the project i have in mind...

What im basically looking to build is a paint grenade launcher to use in paintball games. The objective is to create a pneumatic cannon which can launch a bladder paint grenade a decent distance without enough force to seriously hurt someone. Im also trying to keep it on the smaller and lighter side for improved mobility.

As for the mechanics, i have a basic understanding of what i need to do. There are some things however which i am not sure of such as what air source would be the best to use? (I was thinking 12g co2 cylinders or a co2 tank) What type of valve should i use for a quick fire? ( i was thinking a modded sprinkler valve?) I know this seem like a lot and Im sorry, but im just getting into the whole idea and wanna be safe and do it right. Any suggestions would be greatly appreciated .

One last thing, just for an idea of what im shooting for, check out 4:15 in this video:

[jackssmirkingrevenge]

Welcome to spudfiles

If you're using CO₂ directly, a modded sprinkler valve will become a plastic grenade in its own right, unless your budget allows for a regulator.

A possible route is a quick exhaust valve , it can be relatively small bore compared to barrel diameter since you're using high pressure and not looking to penetrate reinforced concrete. With a slide valve pilot, you could speed up the reloading process, maybe even make a simple bolt action.

Have a careful look throughthis thread for a clearer idea of the principles involved.

[Crna Legija]

i think something like this would suit you perfectly

[conkfa47]

If you're using CO2 directly, a modded sprinkler valve will become a plastic grenade in its own right, unless your budget allows for a regulator.

this was something i worried about when thinking about it. What kind of regulator would suffice for this? Would a normal air regulator from home depot work or would i need one specialized for the pressures of a co2 tank? I also took a look at QEV valves after doing some research and found this; http://www.mcmaster.com/#catalog/117/969/=dt6ul9 from what i have read that's what i would want (section f, 6646k23). Just a question tho, what kind of trigger mechanism would you use for that? Is there a certain button attachment or lever i can use with nice ergonomics?

i think something like this would suit you perfectly

thats along the lines of what im looking for but the back part is a bit awkward looking...is there a way to make that more inline for firing? Maybe like a LAW launcher?

[Crna Legija]

thats along the lines of what im looking for but the back part is a bit awkward looking...is there a way to make that more inline for firing? Maybe like a LAW launcher?

like this, nice and simple just a moded sprinkler valve or with a bit more work you can try make a coax piston valve.

[jackssmirkingrevenge]

like this

A good example, however it needs to be refilled for every shot, annoying if you're not in a protected spot.

this was something i worried about when thinking about it. What kind of regulator would suffice for this? Would a normal air regulator from home depot work or would i need one specialized for the pressures of a co2 tank?

A specialised CO₂ reg would be needed, remember that it needs to resist an input pressure of at least 900 psi.

I also took a look at QEV valves after doing some research and found this; http://www.mcmaster.com/#catalog/117/969/=dt6ul9 from what i have read that's what i would want (section f, 6646k23). Just a question tho, what kind of trigger mechanism would you use for that? Is there a certain button attachment or lever i can use with nice ergonomics?

If you're using less than 400 psi, an ordinary blowgun would suffice, ball valves and slide valves are also an option.

[Lockednloaded]

If you're willing to bump up the pressure some, you can make a really compact gun with metal parts.



This one shoots NERF vortexes a little over 100m at 25BAR

[SP00K]

I made one. 4 inch diameter body with 2 inch barrel coax. Big. As. F***. Make sure you have a sabot or powder (as lubricant) for the grenades, they like to stick to the inside walls of the barrel and shred themselves when firing.

[mattyzip77]

Yes find some way to hold the powder, if it gets up in the mechanics it will slow it down alot, either that or clean it out afterits fired every time!

[jimmy101]

For a CO2 source some kind of pressure reg is pretty much a requirement.

Given the diameter of the barrel and the fairly low target muzzle velocity I suspect you can get away with pretty much any valve (except a ball valve), a generic un-mod'd 3/4 sprinkler valve is probably adequate.