Paintball Machine Gun, A Few Questions

[clemsonguy1125]

I saw a few posted on Spudfiles the other day and got an idea, it was a paintball machine gun. It was a blow forward breach. It seemed to have some dead space. I drew up a diagram of how it works as I understand. Am I misunderstanding how it works. Also where can I get a saftey pop off valve thats pops at 60 psi. I could not find any reasonably cheap ones on ebay.
[youtube][/youtube]
The video

[jackssmirkingrevenge]

Actually, that's a chopped version of clide's diagram

You need a ball valve between your pop-off and sprinkler valve to use this as a trigger, otherwise it will just fire as you fill it.

Our benevolent sponsor has 10 buck safety valves, 140 psi but I'm quite sure you can take these apart and fiddle with the spring.

[clemsonguy1125]

Cool thanks, the ball valve in the back will act as the trigger, I just accidently made it closed when I was drawing the paint pic

[jackssmirkingrevenge]

Cool thanks, the ball valve in the back will act as the trigger, I just accidently made it closed when I was drawing the paint pic

I think you should have a valve between the pop-off and the sprinkler, sprinklers need high flows to reset otherwise they will just honk.

[clemsonguy1125]

Wouldnt it have the highest flow since theres no valve restricting flow to the breech, and the popoff wont pop till 60 psi.

[jackssmirkingrevenge]

When you open the "fill valve", the sprinkler valve will not be sealed, the pressure in the "chamber" needs to be at least 15 psi or so before the valve will stop honking, which will make for a pretty awkard firing cycle.

Your best bet is something like this:

[Gun Freak]

I would replace the pop-off with a modified blowgun-- semi is my taste. This design is definitely on my list...

[clemsonguy1125]

Ok cool, so I guess Ill use a 1/4 ball valve for that

Just found this

[Gun Freak]

You goin' through with the BFB?

[clemsonguy1125]

The what

[Gun Freak]

Blow Forward Bollt....

[jackssmirkingrevenge]

Blow Forward Bolt

[clemsonguy1125]

Yeah why, it looks like a simple build, if I end up building it Ill use it, right now the price is like 50 something bucks so i may need to find so better deals

[Gun Freak]

Beat ya to it But to be fair, I was too lazy to bolden the first letters

@CG1125 just askin' cause I never go through with any of my builds LMAO but yeah, 50 bucks ain't a lot at all, but for such a simple concept I'm sure the cost could be lowered.

[clemsonguy1125]

I was talkin to spudtyrannt and he said the valve would honk even with the BV before the pop off