acetylene

[POLAND_SPUD]

I have an idea.... if I inject some acetylene behind the projectile and fire the gun (pneumatic spudgun) would acetlyene ignite? you know becasue of pressure and/or temperature increase ?
would it improve performance by increasing the speed of gases behind the projectile?

[TurboSuper]

Either that or send shrapnel into your soft, supple flesh.

[psycix]

If you would use a strong steel chamber and barrel, yes it would probaly work.

[BigGrib]

short answer no. long answer no because acetylene will spontaneously ignite over 15 psi and it would just be dangerous to try and do something like that

[POLAND_SPUD]

lol not everyone is using PVC you know.... I use steel all the time.... @ biggrib -> I am thinking about injecting it directly behind the projejtile, into the deadspace... so it's not going to be under pressure before firing the gun

[Novacastrian]

My thoughts are that the mixing of air with Acetylene may dilute it too much, leading to nothing happening at all, to the Acetylene going off with a nice pop and adding much wanted velocity.

The dangers of such a setup include a leak from the chamber (pressurizing the acet too early, going off before you want it too) this could be negated with the use of a reliable burst disc.

The barrel exploding (not really a worry for yourself Mr Metal man!)

The danger of working with Acetylene in the first place.

I think you should design and build such a cannon if you want to, hell isn't the recent 28.8KJ electrothermal gun posted recently just a *little* bit more risky than this idea?

Edit:Grammar

[POLAND_SPUD]

I am thining about this for some time... (since I've realised that pneumatic cannons have certain limitations and since I've seen that spring powered acetylene injected airgun on youtube)
I don't really know if or when I am going to test it... it is just an idea and I wanted to share it with you
I see it as a way to combine the power of hybrids (or at least as a way to give more power to pneumatic guns) with simplicity and rate of fire of pneumatic guns

[DYI]

Here's a quick paint sketch. With a big enough lathe and some skills, it should work. The piston tube is aluminum, so that you can move the steel piston back into place with a powerful magnet. You could put the oxy/acetylene valve at the front, but then it would have to survive detonations. In this design, the only part being subjected to repeated detonations is the tube and the disk holder.



This isn't exactly simple, but your idea as it stands either won't work, or will be rather feeble (by my standards at least )

[Novacastrian]

Nice quick diagram DYI, it looks like a pneumatic on Steroids.
I too thought that a piston would have to be used but my design (in my head) was a little different.

[POLAND_SPUD]

nice diagram... yeah DYI this thing is defienatelly going to work... I wonder if it would work without piston or without rupture disk (i think it is not really needed - an o-ring or something would be enough to stop the projectile from moving down the barrel before acetylene would ignite) becasue what you proposed is acctualy a pneumatic acctuated this --->

when build according to your diagram it would have all the disadvantages of hybride (low rate of fire since the burst disk have to be replaced after each shot & the fact that there has to be proper air&fuel mix before firing)


I have little knowledge to tell whether it would work with acetylene being injected between a firng valve and the projectile and fired with a regular pneumatic spudgun... would acetylene ignite just becasue of pressure and as soon as the air/fuel mix would get right?