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 42 users online :: 5 registered, 0 hidden and 37 guests


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

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

The Team
Administrators
Global Moderators
global_moderators.png CS

First Compressed gas Cannon (rather technical)

Post questions and info about pneumatic (compressed gas) powered cannons here. This includes discussion about valves, pipe types, compressors, alternate gas setups, and anything else relevant.
Sponsored 
  • Author
    Message

First Compressed gas Cannon (rather technical)

Unread postAuthor: mrmagoo » Fri Mar 09, 2007 6:16 pm

OK heres what I have so far:
Power source: Propane from a Colman 16oz bottle (Its roughly 300psi as I understand) stored in a sealed container filled from an airsoft gbb fill valve. The container will be either PVC or ABS (PVC would be nice because it is cheaper, but if ABS is an overall safer design for the specs, I would go with that.)
Barrel will be roughly 20-25" long
Round will be a tennis ball
Fireing mech with be a Quarter turn ball valve
The Barrel will be 3" piping
the container will be 1.5" piping (have some lying around, so its that small for price sake)

The problem is this thing hast to be shooting a tennis ball below 300 feet per second and above 200. does anyone have an idea of how long my gas chamber should be to give me this result?
  • 0


mrmagoo
Private
Private
 
Posts: 3
Joined: Fri Mar 09, 2007 6:04 pm
Reputation: 0

Unread postAuthor: spudthug » Fri Mar 09, 2007 6:34 pm

ummm 2 problems...one dont use propane for a pneumatic gun.....two a tennisball fits WAY to loosely in a 3inch barrel to go more than 20 feet....oh and that isnt at all technical that is a basic cannon gone wrong...look up this stuff around here that wont work at all.......
  • 0

4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
User avatar
spudthug
Brigadier General
Brigadier General
 
Posts: 936
Joined: Mon Feb 26, 2007 9:02 pm
Location: johnsonburg, Pa USA
Reputation: 0

Unread postAuthor: spudthug » Fri Mar 09, 2007 6:35 pm

oh and the container????you mean chamber???you cant power a bigger barrel with a smaller chamber...your gun is a disaster plan...do some research
  • 0

4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
User avatar
spudthug
Brigadier General
Brigadier General
 
Posts: 936
Joined: Mon Feb 26, 2007 9:02 pm
Location: johnsonburg, Pa USA
Reputation: 0

Unread postAuthor: WOW!! » Fri Mar 09, 2007 6:37 pm

NO ABS!!!!!

Go with pressure rated Sch40 PVC, and don't use propane eather. For a tennis ball barrel use 2.5'' Sch40 PVC.


NO ABS IN PNEUMATIC GUNS. Sorry for the caps but I want to make sure you understand this.
  • 0

(\__/)
(O.o)
(> <)
This is Bunny. Copy Bunny into your signature to help him on his way to world domination.

My girl friend says I dont listen, at least thats what I think she said...
User avatar
WOW!!
Brigadier General
Brigadier General
 
Posts: 889
Joined: Thu Mar 16, 2006 9:47 pm
Location: New jersey
Reputation: 0

Unread postAuthor: schmanman » Fri Mar 09, 2007 6:38 pm

what do you mean by "the container"?

the chamber needs to be larger than the barrel.

is this a combustion or a pneumatic?

do you mean a 25 foot log barrel?

do you mind explaining better?

and what is a "airsoft gbb valve"?

and what diameter ball valve?

:?: :?


lots of holes in your design.
  • 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: zeigs spud » Fri Mar 09, 2007 6:47 pm

omg rofl propane??!?!?! roflmfao omg dude i'm sorry but do some research rofl...what a waste of $$ get a bike pump it is safer and cheaper and it uses somthing you have alot of.....AIR!!!!! lol sounds good for a first...besides the Propane!! rofl only time you pressurize an explosive gas for spudding is in a hybrid but you ar nowhere close to safely acomplishing that i'm sorry lol. when u make ur cannon show some pics :D
  • 0

User avatar
zeigs spud
Colonel
Colonel
 
Posts: 657
Joined: Tue Apr 04, 2006 10:39 pm
Reputation: 0

Unread postAuthor: Punstype » Fri Mar 09, 2007 6:48 pm

i think he got his barrel and chamber sizes mixed up,and you cant shoot tennis balls out of 1.5" need to use 2.5"
and you might want to make sure you use PVC for your pneumatic gun because ABS is unsafe. alot of guys gave me some advice because i had made that mistake on my first pneumatic.
  • 0

User avatar
Punstype
Private First Class
Private First Class
 
Posts: 27
Joined: Fri Jan 26, 2007 1:04 am
Location: Hawaii
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: spudthug » Fri Mar 09, 2007 7:11 pm

exactly guys thats what i explained to him look at my post lol i agree with every one of u
  • 0

4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
User avatar
spudthug
Brigadier General
Brigadier General
 
Posts: 936
Joined: Mon Feb 26, 2007 9:02 pm
Location: johnsonburg, Pa USA
Reputation: 0

Unread postAuthor: Hotwired » Fri Mar 09, 2007 7:38 pm

300psi from 1.5 into 2.5 with a 25" barrel

...and the dodgy assumption that air is the same as propane ( :D )

...and some fudging of the valve details :P

You'd need about the same length of chamber as barrel for over 200fps, probably a bit more, say 30".

You'd first want to get pipe that can actually hold 300psi....
  • 0

User avatar
Hotwired
Lieutenant General
Lieutenant General
 
Posts: 2599
Joined: Fri Oct 13, 2006 5:51 am
Location: UK
Reputation: 0

Unread postAuthor: zeigs spud » Fri Mar 09, 2007 8:58 pm

i basicly sugest for ur first penu that u only make a 125psi cannon. for first 300 seems high to me.
  • 0

User avatar
zeigs spud
Colonel
Colonel
 
Posts: 657
Joined: Tue Apr 04, 2006 10:39 pm
Reputation: 0

Unread postAuthor: Insomniac » Fri Mar 09, 2007 10:30 pm

I thought propane liquifies at around 90psi @ room temp.

And NEVER EVER EVER USE ABS IN A PNEUMATIC!!! It can't cope with the rapid pressurization/depressurisation over and over and over again.
  • 0

Last edited by Insomniac on Sat Mar 10, 2007 1:35 am, edited 1 time in total.
I wonder how much deeper the ocean would be without sponges.
Right now I'm having amnesia and deja vu at the same time. I think I've forgotten this before.

Add me on msn!!! insomniac-55@hotmail.com
User avatar
Insomniac
Major General
Major General
 
Posts: 1297
Joined: Mon Dec 18, 2006 3:47 pm
Location: Australia
Country: Australia (au)
Reputation: 0

Unread postAuthor: iknowmy3tables » Fri Mar 09, 2007 11:06 pm

300psi of highly flamable gas in a ABS chamber now thats a really safe spud gun lol
man I really hope he ment that the ABS was for just holding the propane tank.
  • 0


iknowmy3tables
Major General
Major General
 
Posts: 1558
Joined: Fri Dec 15, 2006 3:57 pm
Location: maryland
Country: United States (us)
Reputation: 0

Unread postAuthor: chaos » Sat Mar 10, 2007 12:42 am

well if you are going to attempt to shoot this please video tape it. i like seeing things explode. :lol:
  • 0

User avatar
chaos
Brigadier General
Brigadier General
 
Posts: 1205
Joined: Wed Jan 17, 2007 8:31 am
Reputation: 0

Unread postAuthor: Insomniac » Sat Mar 10, 2007 1:38 am

Oh and you will need pressure rated fittings, NOT DWV!!!
  • 0

I wonder how much deeper the ocean would be without sponges.
Right now I'm having amnesia and deja vu at the same time. I think I've forgotten this before.

Add me on msn!!! insomniac-55@hotmail.com
User avatar
Insomniac
Major General
Major General
 
Posts: 1297
Joined: Mon Dec 18, 2006 3:47 pm
Location: Australia
Country: Australia (au)
Reputation: 0

Unread postAuthor: MrCrowley » Sat Mar 10, 2007 1:47 am

Yeah well I doubt you like seeing people explode :P

Dude, download GGDT(dont ask use google) to find out what diameter chamber and the length of the chamber and barrel to get 200-300fps.


I say a 3"(or 4") chamber 36"(24") long.....2.5" barrel 50" long. And a blow gun acuated sprinkler valve. Pressure 125psi.

I doubt you could get 250fps with a 20" barrel easily.
  • 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

Next

Return to Pneumatic Cannon Discussion

Who is online

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

Reputation System ©'