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Posted: Tue May 13, 2008 2:10 am
by Pyro Ninja
Very nice, Love the power, expecially for such a short(ish) barrel :D

Posted: Tue May 13, 2008 5:40 am
by VH_man
you do realize supersonic golfballs have the same muzzle energy as some anti-aircraft rounds.................

anyway, im proboably going to build a gun off of your "meter" design. i like it alot.

and that 20X mix......... HOLY F*** that was insane........... you did need a thicker burst disk though.

Posted: Tue May 13, 2008 6:39 am
by psycix
Ah you finally posted it DYI :D
Its as impressive as I expected.
Will more vids come?
Exact muzzle velocities? :roll:

Posted: Tue May 13, 2008 7:21 am
by JDP12
wow... that thing is sick and awesome, nice job DYI

Posted: Tue May 13, 2008 8:36 am
by POLAND_SPUD
this is madness :D

BTW we have to make Larda to pressure test some standard iron fittings to get the rough idea about their 'real' pressure rating :wink:

Posted: Tue May 13, 2008 8:53 am
by pat123
wow amazing :notworthy: . taking those fittings to 20x :shock: I am surprised that they stood up to that. I am definitely going to have to upgrade Biohazard. :wink:

Posted: Tue May 13, 2008 9:36 am
by bigbob12345
Wow I just realized those were malleable iron fittings, I didn't read through at first and assumed they were special high pressure ones.
Im very surprised that they held at 20x, Im also surprised that ddt didn't occur.
Well DYI, You really like to push the limits.
I thought using 500psi on the sctbdc was pushing the fittings but this is something else.
Nice job, I guess

Posted: Tue May 13, 2008 2:53 pm
by Ragnarok
POLAND_SPUD wrote:this is madness :D
No. THIS IS SPUDFILES!!!

*Kicks Poland spud into conveniently positioned hole*

Very impressive DYI... If 20x oxy-propane doesn't detonate in 7 chamber diameters, we need a rethink of our detonation theories, although we should still be wary.

Posted: Tue May 13, 2008 3:38 pm
by daberno123
It didn't blow-up, which is great, especially for Kevin, who doesn't have to give you his PS2 :D

That really surprised me that it didn't blow up because of a detonation, which would have seemed inevitable at these mixes. Seems the usual assumptions have been proved wrong.

This doesn't mean everyone should start putting 20x into their hybrids though, and just because this gun survived it doesn't mean everyone who tries it won't be killed.

Still, that was awesome, but not the safest thing to do :twisted:

Posted: Tue May 13, 2008 3:50 pm
by paaiyan
:shock:

Wwwooowww.

Me likey. I want to see what that thing could do to a block of ballistics gelatin.

Posted: Tue May 13, 2008 3:52 pm
by pat123
yeah we need more damage pics. try shooting through 1" steel

Posted: Tue May 13, 2008 4:03 pm
by drex
umm......... WOW. shoot some thing other than water plz. other than that awsomesweetsexycool

Posted: Tue May 13, 2008 4:36 pm
by DYI
I got the epoxy to rebuild the sparkplug, and I did a bit of a redesign to (hopefully) prevent the problem of the entire guts of the sparkplug getting pushed out. The next one will have copper conductors. A 3000 psi rated forged steel union left Georgia on the way to Ontario last night, and hopefully a high pressure rated chamber is in the works as well.

The problem with shooting holes in thick steel is that you need harder steel to do it. I don't have the equipment yet to harden it myself, so I need to buy it. Where I live, that means center punches, which, at $8 a piece, aren't very affordable ammo. I'll try my luck against 1/4" plate with unhardened ammo, but I wouldn't get too excited about it, as this thing doesn't have much more muzzle energy than the SCTBDC did (although at a quarter the weight and a third the length, I think it's a pretty good trade-off).

I've got to work this weekend, but I'll try to take it out and get some shots on Monday. I can't really promise anything, and you have to remember that, at these pressures, I can never count on it surviving the shot.

Posted: Tue May 13, 2008 5:19 pm
by clide
Did you happen to measure the pipe and fittings before and after the shots to check for plastic deformation?

Impressive gun although I must say a little bit insane. It's a bit of a shame that the 20x was just shot into the water.

Posted: Tue May 13, 2008 5:39 pm
by DYI
There's a story behind the different position of the last shot that I'm not going to get into here, but the water was the best target we could find in the nearby area where we could still run the wires behind something sturdy.

As the look of the GHETTOPOD might tell you, this testing wasn't exactly done in a highly planned and controlled manner, so no, there aren't any measurements :roll: