SpudFiles

If only my sigg bottle had a valve stem.

Freezing water is not a good comparison. I think that bottle will be more than fine for a combustion. People have made combustions out of milk cartons and cardboard tubes and they survived more than a few shots at least. This thing will not shatter even if it does fail. It will split open. Just make some handles for it and use it as a combustion and I am willing to bet it will never fail. I'd still trust that sigg bottle over PVC any day.

Poland spud do you happen to know the length and diameter of those 88 gram co2 cartridges... also how hard is it to find an adapter to go from co2 threads to regular npt ones?

Back on thread:
Why not build a regular meter for the gun ( you probably already know the volume, if not just look for some marks in the sides or something its probably measured), add an ignition somewhere in the back and remote fire the first shots... can't take longer than 1 hour to do all this..

@theBOOM
35mm diam and about 19cm long (not including the threads)
volume = 117cm3

they almost fit 3/8" BSP, not ideal fit but you should be able to use them (I am not sure about NPT though)

someone said they are 16mm x 1.5 threads... I've just measured them but I really don't know how to measure threads (I got two numbers, 14mmX1.5 and 15.5mmX1.5 you can guess why

I know that similar threads are used in hydraulics and that you should be able to get adapters from 16X1.5mm (and similar) to BSP (NPT in your case) in places that sell such stuff

well at least I can get them here in europe

Thanks poland spud do you have any idea to what they are rated? More than 1000 psi im guessing?

I couldn't find their rating but it can be assumed that they're rated to at least 900 psi.. IDK how much higher... possibly more but I want to avoid doing what I criticized a couple of hours ago.. so I guess you can find it somewhere if you try really hard

I guess they would make pretty cool chambers for relatively high mix hybrids... of course it would be best to choose a design that would not require you to drill holes in the cartridge...

EDIT
lol I guess there was no need to measure it


http://www.genuineinnovations.com/custo ... ridge.html

So here is a question. I did some calculations based on burnt latke's propane pipe calculator. It seems that for such a small volume chamber I will only need a 1/4X2.27 inch pipe. Question is,how in the world am I going to be able to fit the pressure gauge and the two valves into that small of a space? Is it possible to just main line the propane into the chamber and experiment with the best amount of time to leave the valve open? I have seen a few examples of this around, but I am wondering how effective the method is. I am sure it is less consistent but it may have to do.

Just get 1/4" valves and gauge.

I'm with Moonbogg. As long as it doesn't start to deform after shots, it should be fine for combustion. Perhaps epoxy the brass fitting in there too.

kjjohn wrote:Just get 1/4" valves and gauge.

so I re-looked at the setup. It's doable but the valves will be almost butted to one another.

Also found another bottle for you pneumatic fanatics. It's called a goodlife bottle. It is a double walled stainless steel bottle and the threads are on the outside of the mouth. Can be found at http://www.goodlifebottles.com o think.

Why not just get a 1 1/2 inch galvanized chamber and some standard fittings? seems heaps easier to me...

True. I guess. Why not just buy a paintball gun? I think I'm interested in this hobby because of the possibility of creating something cool. And cool and ugly don't mix for me. Galvanized pipe is just plain ugly. Uglier than PVC to be certain.

Well you can always paint it to make it not look ugly, or if your that stubborn put the frikkin sigg bottle over the steel pipe and glue it on hahhaha yeah I like plain and simple first get a working model then do the aesthetics and stuff...

LOL. Or just get a paintball gun. On another note, I can't get the freaking braided hose anywhere with the correct size fittings to make the propane pipe. AND I can't find the gauge with the regulator on it either. No HD or Lowe's love. I'll try the plumbing supply joint tomorrow.