SpudFiles

JDP12 wrote:if I just backed the original rubber pistons with a steel washer, do you think it would function fine, instead of making a whole new piston?

To be honest I think the stock piston can take it pretty well without modification. If not I'm willing to bet that a simple delrin cylinder with enough pressure behind it to seal without needing any rubber attachment will be an adequate and durable solution.

Further to yesterday's suppressor talk, here's a rough concept for a suppressor incorporating a "shut off valve" operating by the propelling gas pressure.

I just realised I forgot to draw the porting in the barrel but you should get the idea, the gas flows into the chamber and pushes on the two black pistons, clamping them together and blocking off the barrel.

Looks good on paper though I wonder how well it would work in practice as far as the pistons closing before all the gas has escaped is concerned.

JSR..that's genius LOL...

.

Imagine a T-piston valve.
In open position.
Lots of blowby on the piston.

Now place that inbetween your barrel and your valve/burstdisc whatever.

The piston will get sucked onto the barrel as the ammo leaves the muzzle.

Then combine it with your idea.

It would be like one of my repeating valve set-ups ( closing a valve immediately after the shot), but with an additional supersilencer..
taking away the remainder of the sound.

Actually..in your idea it would be easier to leave out the barrel inbetween the two baffles...and just throw in a lightweight bb.
And use only the bottom hole to help it agitate.

Looks good in theory.. my worry is air always takes the path of least resistance, and may very well just flow out the barrel anyway. Air travelling at high speeds does so extremely quickly, my fear is quicker than the pistons can move.
However, I can see this definitely slowing the passage of air throughout the suppressor chamber.

Gonna prototype it?

This would be JSR's simplified version:

That does indeed look sexy, almost worth giving it a go although I think those 2 little pistons would be a sod to reset after each shot.

Brian the brain wrote:Actually..in your idea it would be easier to leave out the barrel inbetween the two baffles...and just throw in a lightweight bb.
And use only the bottom hole to help it agitate.

(started a new thread to avoid hijacking this topic)

Gonna prototype it?

Probably, lathe and mill should make short work of it

That does indeed look sexy, almost worth giving it a go although I think those 2 little pistons would be a sod to reset after each shot.

True, but Brian's variation solves this problem if it's not 100% airtight because it would just reset by gravity. If not, all you need is a bleed valve somewhere on the suppressor body.

I think jsr's design but instead of two rectangular blocks you could just use a bit of silicon tubing to cover the holes it will expand to let out you could poke a small hole in it to bleed out the pressure.

I wanna put a flexible hose on my fridgy, would a braided stainless hose work?

They'll work. The ones you get at Home Depot are supposedly "rated" to 1000 PSI.

Ok thanks Mark!

i have a question that how to make a glue gun piston for a pen gun? i try making it and it end up stuck and i cant take it out

How many times have you asked that question?

quick question pour vous tout. im working on a design for a bolt action .50 cal and it will use a QEV and a slide vlave. my air chamber will be turned on a lathe and steel, about 1 inch. probably operating at high pressure (hopefully 400-500 if i can get a fridgy) jsr has linked for us in the past this qev
http://www.ebay.com/itm/1-2-Inlet-Outle ... 0689947756

and this slide valve
http://www.ebay.com/itm/Silver-Tone-Blu ... 1599wt_974

will these have enough air flow to be a efficiant? if not what would be better to use?

They sucks! I bought both of them, just a wast of money.