Login    Register
User Information
Username:
Password:
We are a free and open
community, all are welcome.
Click here to Register
Sponsored
Who is online

In total there are 46 users online :: 5 registered, 0 hidden and 41 guests


Most users ever online was 218 on Wed Dec 07, 2016 6:58 pm

Registered users: Bing [Bot], Google [Bot], Google Adsense [Bot], MSNbot Media, Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

S.W.A.T gun by schmanman

Built a pneumatic cannon? Then post it here! This section is for completed, finished cannons that you have built. Please include pictures and information.
Sponsored 

does it look evil?

heck yes
0
No votes
no
0
No votes
anything but evil!
0
No votes
anything but evil!
0
No votes
anything but evil!
0
No votes
 
Total votes : 0
  • Author
    Message

Unread postAuthor: schmanman » 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.
  • 0

Persistence is a measure of faith in yourself
User avatar
schmanman
Major General
Major General
 
Posts: 1685
Joined: Sat Mar 25, 2006 12:28 pm
Location: Michigan,U.S.A
Country: United States (us)
Reputation: 0

Unread postAuthor: Demon » 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.
  • 0

User avatar
Demon
Colonel
Colonel
 
Posts: 743
Joined: Sun Apr 13, 2008 8:46 am
Reputation: 0

Unread postAuthor: STHORNE » Thu Apr 17, 2008 6:08 pm

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

against the rules btw.
  • 0

Forum Rules - follow them or else!
“Happiness is the meaning and the purpose of life, the whole aim and end of human existence”
User avatar
STHORNE
Donating Member
Donating Member
 
Posts: 1208
Joined: Wed Feb 14, 2007 7:50 pm
Location: Kewaunee, Wisconsin
Reputation: 0

Unread postAuthor: bigbob12345 » 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
  • 0

User avatar
bigbob12345
Major General
Major General
 
Posts: 1516
Joined: Sat Dec 01, 2007 9:13 am
Location: Mercer Island,Washington
Reputation: 0

Unread postAuthor: DYI » 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
  • 0

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.
User avatar
DYI
Lieutenant General
Lieutenant General
 
Posts: 2861
Joined: Sat Jul 07, 2007 8:18 pm
Location: The People's Republic of Canuckistan
Country: Turks and Caicos Islands (tc)
Reputation: 9

Unread postAuthor: MrCrowley » Thu Apr 17, 2008 11:47 pm

Fair enough, the posts remain. Discuss at free will :)
  • 0

User avatar
MrCrowley
Moderator
Moderator
 
Posts: 10207
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Country: New Zealand (nz)
Reputation: 4

Unread postAuthor: noobyspud » Wed Oct 22, 2008 5:47 am

man that is .....awesome. will you be presenting us with a video ?
  • 0


noobyspud
Private
Private
 
Posts: 23
Joined: Fri Jul 18, 2008 11:21 am
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: Ragnarok » 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.
  • 0

Does that thing kinda look like a big cat to you?
User avatar
Ragnarok
Chief of Staff
Chief of Staff
 
Posts: 5339
Joined: Tue Dec 19, 2006 8:23 am
Location: The UK
Reputation: 8

Unread postAuthor: schmanman » 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 crap 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
  • 0

Persistence is a measure of faith in yourself
User avatar
schmanman
Major General
Major General
 
Posts: 1685
Joined: Sat Mar 25, 2006 12:28 pm
Location: Michigan,U.S.A
Country: United States (us)
Reputation: 0

Unread postAuthor: Ragnarok » 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.)
  • 0

Does that thing kinda look like a big cat to you?
User avatar
Ragnarok
Chief of Staff
Chief of Staff
 
Posts: 5339
Joined: Tue Dec 19, 2006 8:23 am
Location: The UK
Reputation: 8

Unread postAuthor: schmanman » 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.
  • 0

Persistence is a measure of faith in yourself
User avatar
schmanman
Major General
Major General
 
Posts: 1685
Joined: Sat Mar 25, 2006 12:28 pm
Location: Michigan,U.S.A
Country: United States (us)
Reputation: 0

Unread postAuthor: covey12 » Mon Feb 16, 2009 12:17 pm

how do you put the 4" barrel on there, it must be hard
  • 0

User avatar
covey12
1st Lieutenant
1st Lieutenant
 
Posts: 260
Joined: Sat Aug 23, 2008 4:36 pm
Reputation: 0

Unread postAuthor: Brian the brain » 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!
  • 0

User avatar
Brian the brain
Moderator
Moderator
 
Posts: 3494
Joined: Mon Dec 05, 2005 2:06 am
Location: Holland
Country: Netherlands (nl)
Reputation: 29

Previous

Return to Pneumatic Cannon Database

Who is online

Registered users: Bing [Bot], Google [Bot], Google Adsense [Bot], MSNbot Media, Yahoo [Bot]

Reputation System ©'