SpudFiles

plastic hybrid = bad. metal hybrid = good.

Do yourself a favor, and regain your confidence in hybrids at the same time - take a look around at any of the hundred or so Big Box store bought threaded steel fitting hybrids on this site. They can easily take up to a 10X mix, and many have pushed it past that. Don't make a plastic hybrid again though... please don't. haha.

Gun Freak wrote: Is DDT at all a possibility here? I mean it did survive a few shots before... Just something that came to me, I'm not at all knowledgeable about it.

DDT is exactly what I was thinking. I havent found much information about propane being able to detonate so I might try to setup a rig to test in a controlled enviornment if propane under pressure and confinement could go DDT with various different initiations like a common spark gap or exloding bridge wire. Also the reason I suggested it seemed way more powerful was due to the huge blast it created. It could just be a case of having the pvc rupture and releasing all the energy at once kind of like a pipe bomb. Something tells me it was more than that, and having a bit of experience working with explosives this seemed way to intense for a deflagration.

I deffinatly do want to build an all steel hybrid in the future, and will take much more safety precautions but I have a few other projects on my hands right now and all my spare cash is going into an experimental high pressure QEV gun. I scored a 3000psi scuba tank filling compressor, and a nice big 4500psi nitrogen tank for it!

If nothing else this was a priceless learning experience about the dangers of this kind of stuff, and the importance of proper safety gear. Even 100psi in a pvc air chamber can be horrific if the chamber were to rupture. Its got me thinking of possible alternatives to pvc for lower pressures like 100-200psi that will not shatter and splinter if it fails. Any ideas?

I don't think you got DDT... Never on record here anybody got a DDT at such a low mix, even with additional oxygen. I remember one member here may got a DDT (Larda) but that was pure oxy/propane at mix 100... PVC accidents however, plenty out there
3000 psi is no joke, mix 10 hybrids don't go much higher than 1000 psi. At that pressure level standard pipe fittings are no longer safe, ball valves will leak etc... You probably will need every part custom made. From a exploded PVC hybrid to a 3000 psi pneumatic it's quite a jump, without caution and knowledge the second is no less lethal than the first.
Copper fittings are good for <1000 psi stuff, also lighter than steel/galvanized iron. Don't know if the price it's right in your area though.

wyz2285 wrote:I don't think you got DDT... Never on record here anybody got a DDT at such a low mix, even with additional oxygen. I remember one member here may got a DDT (Larda) but that was pure oxy/propane at mix 100... PVC accidents however, plenty out there
3000 psi is no joke, mix 10 hybrids don't go much higher than 1000 psi. At that pressure level standard pipe fittings are no longer safe, ball valves will leak etc... You probably will need every part custom made. From a exploded PVC hybrid to a 3000 psi pneumatic it's quite a jump, without caution and knowledge the second is no less lethal than the first.
Copper fittings are good for <1000 psi stuff, also lighter than steel/galvanized iron. Don't know if the price it's right in your area though.

Although this was my first hybrid, most of my experience for that past decade has been with high pressure pnuematics. Ive done several 2000-3000psi cannons and PCP rifles but never with a home made QEV, and thats what my current project will be. All parts must be special ordered and are pretty pricey but have ratings of 3000 psi working pressure and burst pressure several times that, so I am more confident with them.

Ive done several 2000-3000psi cannons and PCP rifles but never with a home made QEV, and thats what my current project will be. All parts must be special ordered and are pretty pricey but have ratings of 3000 psi working pressure and burst pressure several times that, so I am more confident with them.

Impressive! Care to show them?

wyz2285 wrote:Impressive! Care to show them?

+1

PVC degrades with repeated abuse. My Mouse Musket an air cannon used to break pistons on a relatively predictable schedue of about 1 per year. Just because your PVC passed the intial stress test, don't expect it to remain safe over time.

noname wrote:Been there done that:


Hooray for PVC grenades!

Oh dang! SCH 80 too! Well... my old hybrid is now a plain combustion launcher. I never fired it anything but remotely. I would guess I put around 100 shots out of it and never had issue but it looks like I may be holding a proverbial (and not so proverbial) time bomb.