What about a bigger thicker o-ring? Or possibly a harder compound to the o-ring

Not only diameter different end to end but also around the inner curcumference of the pipe. My sch 80 "seamless" still has high and low spots. I will probably end up going with a machined piston at some point for overall ease of use. I wanna try to keep as much of the work in house as possible at fi...

Sch 80 1 1/4 id 1.267 and 1.255 for each end. Sch 80 1 1/2 id 1.479 and 1.490 for each end. I think that would be enough to blow my o-rings out. Im getting the 1 1/2 machined to 1.5 all the way through. If my washer and bolt setup similar to yours doesnt work then i will have an aluminum one machined.

I dont know if you guys in New Zealand get different grade stuff from what we do in the states but pipe here isnt as uniform. I checked the id of a sch 80 seamless pipe nipple and it varried from one end to the other a bit. It could be there is a low spot where the force due to the pressure acts on ...

Interesting bumper. Have you checked the diameter of your piston cylinder. If it isnt very uniform you will have trouble getting an oring to seal whether the washers are close to the diameter or not.

Just curious as to if you use a bumper of any sort for the rear of your piston to protect the pilot area from shock.

Thanks tech. If i go any further with the sytem I will do that for sure.

DHall, I dont know what your refering to when you say "mic the system". I didnt allow for fatigue or moments and would appreciate your explanation of what you mean(would you please elaborate). As well i do not plan on using the pipe and fittings on any gun that can develop 5ksi as this was just a te...

yea I finished a 1.5'' chamber burst disk hybrid and shot it a few times at 5x but wasnt happy with the irregularities in the stungun/sparkplug system. I think the sparkplug had too much internal resistance. Im going whole hog now and just planning on a piston hybrid. Hoping for a fridge compressor ...

I just pressure tested a piece of seamed black iron pipe for burst pressure. My setup was two caps and a 1''x2'' pipe nipple. One of the caps had a 1/4''npt hole in it for the 0-5000psi pressure gauge and also a 1/4''x28 hole in it for the grease zerk. I filled it with manual transmission oil and th...

I am considering using an 80 cf empty high pressure cylinder. In the attached file i would cut the neck to accept 3'' pipe inside of it. It would be a short stub of pipe with a coupling on it to house the burst disk. The coupling as well as the pipe would be welded to the cylinder and this area woul...

It all depends on what you want. If its loud and you like it that way then keep it how you have it. A 15' 1.5'' sdr 21 barrel gives you about a .89:1 c:b ratio which would squeeze a bit more power out of the gun. You have to consider the fact that barrels that long, unless sleeved in 2'' sch 80(in w...

Yes it would burn just fine. Instead of charging with 5x worth of air at whatever pressure you need you are eliminating the extra nitrogen. Since you are just getting rid of extra non reactive gasses it would burn but not with the same characteristics. Due to lack of a "buffer gas" so to speak your ...

I checked and I don't think I will have a problem with barrel droop. I have a gun that uses a 15' 3 inch pvc barrel and it does droop some but I will be using sch40 steel on this hybrid (of course ) and it doesnt seem like there will be a problem.

Spudtyrrant, you must have misunderstood as i didn't mean 1000psi before ignition. What i meant is that a disk that would burst at 1000psi would fail at much less pressure due to lack of something to grab onto in the groove in the coupling. This would occur post-ignition. I have done my homework and...