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supersonic?

Posted: Mon Mar 03, 2008 1:00 pm
by SpudFarm
supersonic yeah thats right.
there has been many people saying (i go supersonic no) but no one can really say yes for certain if i ask (have you gone to mach1?)

so does anyone KNOW that they have gone supersonic? i pretty much doubt that but have anyone on this forum measured it or know of a web site where it is a video or pic of a supersonic shot on a coronagraph with a home made gun that uses gass or compressed air (or both)?

Posted: Mon Mar 03, 2008 1:08 pm
by jackssmirkingrevenge
This is the closest I've ever got, and i still have to test it with lighter projectiles now that I have a better chrony.

Posted: Mon Mar 03, 2008 1:12 pm
by MaxuS the 2nd
Spanerman went supersonic with his hybrid on a 6x mix if I remember correctly.

What's so special about it when many other people have gone for it.

The ultimate goal would be 1" of hardened steel plate, pierced.

Posted: Mon Mar 03, 2008 1:12 pm
by Jared Haehnel
I know that many hybird cannons are able to propell an object to mach 1... yby the very nature of the gun it would be relativly easy. Easier to achieve using light projectiles.

You probably would not get supersonic from a regular pnuemtic becuase air doesn't detonate (or expand faster then SOS) but I could be wrong there. You can get real close but I doubt you'd reach it. Perhaps with helium or some other lighter gas...

A normal combustion is out of the question...even using acetelyn which I don't reccomend I doubt you will get there.

If you want proof sorry I can't give you any although. Just pure speculation. I read on Spud Tech about a gun that sent a spud faster then the SOS. That was almost three years ago though.

Posted: Mon Mar 03, 2008 1:19 pm
by jackssmirkingrevenge
Jared Haehnel wrote:You probably would not get supersonic from a regular pnuemtic becuase air doesn't detonate (or expand faster then SOS) but I could be wrong there. You can get real close but I doubt you'd reach it.
The commercially available AirForce Condor goes supersonic with compressed air alone, it's entirely possible.

Posted: Mon Mar 03, 2008 1:33 pm
by SpudFarm
yeah:)
my chrony was sent today or tomorrow so i think i get it this week.
then i see if my hybrid can do it (i will post a topic with results of my pneumatic and hybrid)

didn't joel do it with the "tornado simulator" ? my chrono btw click the image and that is norwegian:)

Posted: Mon Mar 03, 2008 1:46 pm
by DYI
Jared, it is easily possible with a normal combustion, moreso than with a pneumatic really. You just need to build it big enough.

dongfang went supersonic with an atmostpheric combustion, and considering that the gases in a combustion's chamber have an SOS of well over 2000 fps, it isn't really that amazing.

Air can expand as fast as its particles can move, 500 m/s (Mach 1.46) on average. Although formation of shockwaves in non-frictionless bores and valves can be a problem, the Airforce Condor overcomes this by shear brute force, as can any properly built airgun with high flow and high enough pressure.

As far as actual proof, Spudinator has a picture of his chrony reading over 1400 fps from a shot with one of his hybrids. I've never seen a video of a supersonic chrony reading though.

1" hardened steel plate would be an interesting goal, I think Killjoy should try it with FEAR. My new upgrades should be able to get a 150 gram holepunch or similar into the trans-sonic range, but I doubt even that would do it. Maybe the [redacted] project though...

Posted: Mon Mar 03, 2008 1:49 pm
by Jared Haehnel
I stand corrected.... thanks :)

Posted: Mon Mar 03, 2008 3:05 pm
by SpudFarm
okei i am going to PM spudinator to get the pic:- P
and then i am going to sit looking out over the roads to look for my chrony (can't wait for it)

Posted: Mon Mar 03, 2008 3:07 pm
by SpudUke5
Wow jdr that really sucks because you were only 12 fps from Mach 1 (1116 fps approx.)

I really think that this is cool, but im not in a rush to do it. I would like to witness a spudgun go supersonic, which would be interesting.

As soon as i get more money, i should be able to finish my 4 inch piston valve which has been postponed due to weather, but today is a really nice day outside so im going to shoot my coaxial piston. :D

Just love spring :)

Posted: Mon Mar 03, 2008 3:09 pm
by Ragnarok
DYI wrote:Air can expand as fast as its particles can move, 500 m/s (Mach 1.46) on average. Although formation of shockwaves in non-frictionless bores and valves can be a problem, the Airforce Condor overcomes this by shear brute force, as can any properly built airgun with high flow and high enough pressure.
I've been thinking about it, and I reckon if I ever get my arse in gear and get more pressure in HEAL, supersonic wouldn't be impossible. Firstly, it's got an incredibly powerful valve and should have lots of pressure.

...not to mention the mods I've just finished on the barrel and valve interior - the bore is now as close to frictionless as is possible - the inside has been polished to a mirror shine, and I finished applying a Teflon lubricant to the inside of the bore earlier. If that's not near frictionless, I don't know what is.

30-35 bar, high flow valve, nearly frictionless barrel and valve... it could work.
Of course, with an evacuated bore it would be easy, but that seems a bit like cheating.

Posted: Mon Mar 03, 2008 3:17 pm
by SpudFarm
if HEAL goes supersonic let us know...

Posted: Mon Mar 03, 2008 3:59 pm
by tomthebomb137
I was thinking about a supersonic pnuematic, it was a dual piston valve piloted with sprinklers and it also had a massive chamber, and a very long barrel, im not sureif it would accually do it, but theres always a chance :D

Posted: Mon Mar 03, 2008 4:05 pm
by SpudFarm
go on with the gun and show us :)

Posted: Mon Mar 03, 2008 4:50 pm
by Ragnarok
spudfarm wrote:if HEAL goes supersonic let us know...
Of course I will. Might take a while to sort though, I've got so many things I want to do, and so little time - I keep losing track of things.