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 74 users online :: 4 registered, 0 hidden and 70 guests


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

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

The Team
Administrators
Global Moderators
global_moderators.png CS

Advanced Combustion FPS And Foot Pounds Of Energy?

Post questions and info about combustion (flammable vapor) powered cannons here. This includes discussion about fuels, ratios, ignition systems, safety, and anything else relevant.
Sponsored 
  • Author
    Message

Advanced Combustion FPS And Foot Pounds Of Energy?

Unread postAuthor: spudkilla224 » Tue Jan 27, 2009 9:49 pm

Hello, i am in the process of making a Advanced combustion with a 30" long 3 inch diameter pipe, and a 2" diameter by 5 foot long barrel. I am using metered propane at 35 psi.

I was wondering how many fps i could shoot a 100 gram slug, and how many Foot Pounds Of Energy My Cannon Should Have?
  • 0


spudkilla224
Corporal
Corporal
 
Posts: 65
Joined: Wed Mar 19, 2008 8:04 pm
Reputation: 0

Unread postAuthor: starman » Tue Jan 27, 2009 10:35 pm

Have you tried HGDT? It makes these kinds of calculations rather trivial.

If you used a 65 psi burst disk and 3 spark gaps, 3.5 oz projectile, 2" inch bore, it looks like you would be at 834 ft*lbs and velocity of 493 ft/sec. Rather nice c:b ratio of 1.12:1 as well.
  • 0

User avatar
starman
Donating Moderator
Donating Moderator
 
Posts: 3041
Joined: Wed Dec 12, 2007 12:45 am
Location: Simpsonville, SC
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Wed Jan 28, 2009 12:07 am

starman wrote:it looks like you would be at 834 ft*lbs


That's almost the same as a three round burst from one of these, so be careful ;)
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: starman » Wed Jan 28, 2009 12:28 am

jackssmirkingrevenge wrote:
starman wrote:it looks like you would be at 834 ft*lbs


That's almost the same as a three round burst from one of these, so be careful ;)


That's also the range of force on one of my trip thunder golfball shots.

Image
  • 0

User avatar
starman
Donating Moderator
Donating Moderator
 
Posts: 3041
Joined: Wed Dec 12, 2007 12:45 am
Location: Simpsonville, SC
Reputation: 0

Unread postAuthor: trigun » Wed Jan 28, 2009 12:31 am

starman i thought you used propane ?
  • 0

User avatar
trigun
Master Sergeant
Master Sergeant
 
Posts: 161
Joined: Mon Jan 26, 2009 11:21 pm
Location: Illinois
Reputation: 0

Unread postAuthor: starman » Wed Jan 28, 2009 12:47 am

trigun wrote:starman i thought you used propane ?


I've used them both equally successfully. I switched to MAPP at the Christmas shootings and it offers a small but slightly noticable performance thump. You need a little more MAPP than propane...I just upped my regulator setting from 68 to 75 psi and that was about right.
  • 0

User avatar
starman
Donating Moderator
Donating Moderator
 
Posts: 3041
Joined: Wed Dec 12, 2007 12:45 am
Location: Simpsonville, SC
Reputation: 0

Unread postAuthor: trigun » Wed Jan 28, 2009 12:53 am

so the mapp is better maybe i'll upgrade. I inspected your cannons farther and saw what you were talking about with the male to 4-2 reducer it looks so clean !
  • 0

User avatar
trigun
Master Sergeant
Master Sergeant
 
Posts: 161
Joined: Mon Jan 26, 2009 11:21 pm
Location: Illinois
Reputation: 0

Sponsored

Sponsor
 


Return to Combustion Cannon Discussion

Who is online

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

Reputation System ©'