Author Topic: New BP Cannon  (Read 801 times)

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Offline mshick

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New BP Cannon
« on: August 08, 2008, 05:41:52 PM »
I just built a new bp cannon out of a solid steel pipe with 1/2 walls. I have fired it a few times with 5 tbl spoons of bp and it sounds great. Question, I thought I read somewhere here that if you put a small baggie of gas on top of the bp, you would get a nice fireball with the boom. Is this safe to do or can the added gasoline increase the psi in ther pipe? I just don't want to get crazy but it would make a nice effect.

Mike

Offline GGaskill

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Re: New BP Cannon
« Reply #1 on: August 08, 2008, 07:11:49 PM »
What is the bore of your new cannon?  If the walls are 1/2", the bore over the poswer chamber shouldn't be more than 1/2" for a safe design.  We really recommend against the use of pipe (meaning stuff designed for water) as cannon making material.  You should look up the strength of pipe on the internet; you will find that the larger sizes are rated at less than 1000 psi which is kind of (a lot) weak when dealing with powder pressures. 

Mixing gasoline and black powder is a practice that is frowned upon by most of this forum.  It is recommended that you not do it.
GG
“If you're not a liberal at 20, you have no heart; if you're not a conservative at 40, you have no brain.”
--Winston Churchill

Offline Cat Whisperer

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Re: New BP Cannon
« Reply #2 on: August 09, 2008, 01:19:09 AM »
Mike - WELCOME to the board.

Don't mess with gas unless you WANT us to read about you in the national news.

Safety is not up for negotiation.  That includes design of the cannon as well as proper loading and firing practices.

I have seen a cannon explode.  There's not much you can do after the fact.

We're here to encourage safe, legal fun with blackpowder cannons and mortars - stick with that and we will enjoy eachothers' experiences and company.

Again, WELCOME!




I just built a new bp cannon out of a solid steel pipe with 1/2 walls. I have fired it a few times with 5 tbl spoons of bp and it sounds great. Question, I thought I read somewhere here that if you put a small baggie of gas on top of the bp, you would get a nice fireball with the boom. Is this safe to do or can the added gasoline increase the psi in ther pipe? I just don't want to get crazy but it would make a nice effect.

Mike
Tim K                 www.GBOCANNONS.COM
Cat Whisperer
Chief of Smoke, Pulaski Coehorn Works & Winery
U.S.Army Retired
N 37.05224  W 80.78133 (front door +/- 15 feet)

Offline mshick

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Re: New BP Cannon
« Reply #3 on: August 09, 2008, 11:48:02 AM »
Thanks guys. I will leave that alone.

Mike

Offline dan610324

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Re: New BP Cannon
« Reply #4 on: August 09, 2008, 02:06:12 PM »
hi mike and welcome here .
always nice to see new cannon maniacs here   ;D
but even if Im an maniac I still like to be secure when Im dealing with explosives .

please forget tha gasoline , whats your real interest ?? cannons or flame throwers ??

please send some photos and dimensions on your cannon

5 tablespoons are much blackpowder , please tell me exact meassurements of your cannon .
sorry to say but Im afraid that you maybe are in an great danger when firing that gun .
cat didnt kidding when he talked about reading about your death in the news .
please let us know the dimensions and how you breach plug construction is .

half an inch of steel is a lot , but is it an seamless pipe or not ??
and if the bore is larger than half an inch it aint enough .
I assume it is when you use as much bp as 5 spoons . or its an extremely long barrel   ;D ;D

nobody here want to be a pain in your a_s . but if we can help you to have some more knowledge about cannon safety and maybe even save your and others life we have reach our goal .
cannons is fun , but used and build without the right knowledge they are very dangerous .
there is to many stories in the news about exploding "cannons" , some are one end open pipe bombs , some are nice cannons loaded with smokeless or way to much bp . doesnt matter what , both are dangerous .

we dont say no no to building cannons , BUT IS IT AN CANNON OR AN ONE END OPEN PIPE BOMB YOU GOT ??
Dan Pettersson
a swedish cannon maniac
interested in early bronze guns

better safe than sorry

Offline cannonmn

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Re: New BP Cannon
« Reply #5 on: August 10, 2008, 12:28:42 AM »
The Hollywood special effects people use improvised black powder mortars to make the huge fireballs you see in movies (as always we caution do not try tihis at home unless you know exactly what you are doing, we're only putting the info here for educational purposes!)

Their mortars use very little black powder, just enough to launch the fuel that makes the flames, which is a dry chemical called benzyl peroxide.  That's the only safe gasoline substitute that can be shot out of a cannon.  It makes no fumes like gasoline, and is stable until ignited by the black powder, after which it burns up pretty quickly in the air with a nice photogenic red-yellow flame.