S.W.A.T gun by schmanman

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.

does it look evil?

heck yes
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no
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anything but evil!
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anything but evil!
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anything but evil!
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schmanman
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Fri Apr 20, 2007 6:51 pm

recruit wins! I ment cat food.

sleekz, nope, in fact is is deadly accurate, and It has a scary good spread pattern.

I shot through the same hole 5 times once, just to see If I could.
the only reason I did'nt keep going is because I wanted to shoot more holes in other stuff.
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Demon
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Thu Apr 17, 2008 6:05 pm

the compression chamber is not enough big for the barrel
so the psi at the end of the barrel will be like - 10 and will make the potato going more slowly at the end of the barrel.
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STHORNE
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Thu Apr 17, 2008 6:08 pm

EDIT: Demon, you know you are kicking up an old thread...

against the rules btw.
Forum Rules - follow them or else!
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bigbob12345
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Thu Apr 17, 2008 6:14 pm

Demon wrote:the compression chamber is not enough big for the barrel
so the psi at the end of the barrel will be like - 10 and will make the potato going more slowly at the end of the barrel.
You are wrong BTW
The barrel could be twice as long and it would still be gaining speed
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DYI
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Thu Apr 17, 2008 7:11 pm

The projectile won't start decelerating until atmospheric pressure and friction overcomes the pressure behind the round. In this case, the air chamber is actually quite a bit bigger than it needs to be for the barrel size;

Chamber volume: ~ 3 400 ci
Barrel volume, with largest barrel: ~ 1 500 ci

Volume of gas in chamber at 40 psi fill pressure: 12 700 ci
Pressure of entire system when projectile is at muzzle: 38.1 psia, quite a bit more than the 14.7 psia that the atmosphere is pushing back with, meaning that the round is still acclerating unless the friction is absurdly high.

I know that I'm aiding in kicking up a dead topic, but the SWAT gun never dies :D
Spudfiles' resident expert on all things that sail through the air at improbable speeds, trailing an incandescent wake of ionized air, dissociated polymers and metal oxides.
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MrCrowley
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Thu Apr 17, 2008 11:47 pm

Fair enough, the posts remain. Discuss at free will :)
noobyspud
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Wed Oct 22, 2008 5:47 am

man that is .....awesome. will you be presenting us with a video ?
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Ragnarok
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Wed Oct 22, 2008 6:50 am

noobyspud wrote:man that is .....awesome. will you be presenting us with a video ?
There are already a number out there - here and there across the forum - but I doubt you will be seeing any new ones, the maker decided to quit the hobby.
Does that thing kinda look like a big cat to you?
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schmanman
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Fri Jan 30, 2009 6:13 pm

I havent quit, I've just.... slowed down. the swat needs about $150 iin parts to become operational again, and at this point i would rather put it into a dirtbike or quad.

while I enjoy blowing things up/shooting things, I think i enjoyed the construcion of the guns just as much, if not more. I enjoy the raw mechanical aspect most!

internal combustion engines are amazng. improving power and efficency, and adapting them to various applications has proved to be a blast! just what the doctor asked for...


I buy old motorcycles and quads for a song and a dance, fix the shit out of them, and kick my friend's $2500 powersports vehicles asses, that are 15-20 years newer, with a $700 dollar piece of machinery I built myself.

it's very gratifying and amazingly fun!

my current bike goes about 80 mph, and I bought it off craigslist for $200
it was in several tupperware tubs. I put it together, custom welded the exaust pipe, since I fit a engine twice as big as the one the bike orriginally came with into the frame. then I fixed/built/installed anything the bike was missing, but new tires and handlebars on it, and I am still improving! I eagerly await the muddy spring! :P

here's some pictures of it, although since this time I've added a plethora of parts to this bike.

http://s343.photobucket.com/albums/o442 ... IM2129.jpg

http://s343.photobucket.com/albums/o442 ... IM2132.jpg
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Ragnarok
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Fri Jan 30, 2009 6:25 pm

schmanman wrote:I havent quit, I've just.... slowed down.
Nobody ever does quit fully.
While I enjoy blowing things up/shooting things, I think i enjoyed the construction of the guns just as much, if not more.
In some ways, I agree. It's great to see the results, but the building is just as much fun.

Unfortunately, the building of them is also quite a lot more expensive... (Read: Hundreds of £, $ or € for a really meaty cannon, where as a shooting session is, usually at least, some cheap ammo and targets - many of which can be things destined for the rubbish bin.)
Does that thing kinda look like a big cat to you?
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schmanman
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Fri Jan 30, 2009 6:29 pm

yeah, true.

although it can be pricy, motor vehicles are a great time!

and to hop on the bike, kick the engine over, and go off and jump and race and ride with your friends is wonderful.
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covey12
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Mon Feb 16, 2009 12:17 pm

how do you put the 4" barrel on there, it must be hard
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Brian the brain
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Mon Feb 16, 2009 4:12 pm

And suddenly the biggest pneumatic on spudfiles is alive and kicking again.

Nice to see you are still around!

This thread deserves a sticky btw.

Especially interesting for the noobs.This thing is a classic!
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