Video-Black powder cannon project

[brushhippie]

THIS IS NOT INTENDED TO FIRE PROJECTILES, DO NOT TRY THIS. I found this piece of pipe out in the scap pile so I thought I would try my hand at building a black powder cannon...I started with a piece of what I believe to be schedule 120 seamless pipe about 3 feet long and welded two 3/8s plates over the end and decided to test it before I did any more to it, so I put 250 grains of my powder in it and tamped a newspaper wad over it and boom! She barks pretty good! I went up to 350 but it was blowing the powder out before it could burn up...so 250 seems to be the sweet spot so far......there are some dirty words in this one so if that might offend you...dont watch...but if you want to see something extremely cool...check it out!
http://youtu.be/FvVB_7O86ZA

 

[M-Cameron]

I found this piece of pipe out in the scap pile so I thought I would try my hand at building a black powder cannon...I started with a piece of what I believe to be schedule 120 seamless pipe about 3 feet long and welded two 3/8s plates over the end and decided to test it before I did any more to it, so I put 250 grains of my powder in it and tamped a newspaper wad over it and boom! She barks pretty good! I went up to 350 but it was blowing the powder out before it could burn up...so 250 seems to be the sweet spot so far......there are some dirty words in this one so if that might offend you...dont watch...but if you want to see something extremely cool...check it out!

that part has me a tad concerned.....

honestly, pipe is cheap....hospital bills are not.......i would rather buy new pipe with a known pressure rating rather than use some mystery steel.

 

[brushhippie]

Well what I meant..I guess is I think they call it schedule 120...I know its 7/16 thick walled and I know that 250 grains of powder are not going to produce enough pressure to compromise it without a heavy heavy projectile. The walls of the cylinder in my 60 are .085" thick and I put 35 grains in it firing a projectile that weighs better than twice what the powder weighs.....Im not concerned...as I have said before its not for the faint of heart.....most experiments are dangerous, so precautions are taken till tests prove it reliable.

edit- It is schedule 80 pipe and will handles pressures up to 6800 psi (thats xs) xxs doubles the pressures...so 250 grains of powder spread over a 2 1/4" area would mean it would have to exceed 6800psi in an area maybe 1/4" thick?...no way man.

 

[Rojelio]

golf ball cannon

brushhippie, I had the same thing in mind. Another way to use up all this homemade powder we been making.

I'm going to build a golf ball cannon. The tubing I ordered for the project is
1.75" ID 4130 chromoly steel.

Golf balls are 1.680" diameter, but, I figure with a thick patch it should seal the bore pretty good.

I beleive this material should hold the pressure. Here are the specs.

4130 (Chromoly) Normalized Alloy Steel
Minimum Properties Ultimate Tensile Strength, psi 97,200
Yield Strength, psi 63,100
Elongation 25.5%
Rockwell Hardness B92

I think it'll be a fun project.

 

[brushhippie]

I think the next one I build will be that size (although golf balls aint cheap) I think they would make great projectiles! Let us know how it turns out!

 

[BADUNAME30]

Too
much
fun !!!!!!!!!

I think the next one I build will be that size (although golf balls aint cheap) I think they would make great projectiles! Let us know how it turns out!

Mmmm... wonder how far a 'launched'
golf ball would bounce off of a hard surface.

 

[Rojelio]

Mmmm... wonder how far a 'launched'
golf ball would bounce off of a hard surface.
__________________

Ha Ha, Yeah, like in the movie "Tin Cup". I love that movie!

 

[rodinal220]

Two end plates welded like that is extremely dangerous and not a sound design.
Use known alloys like 1018,4140,4130 and the like for proper cannon barrels. Seamed(I know you said seamless,make sure) anything cannot and should not be used for liners or barrels.A powder chamber adds strength.


A pinned and welded plug of several inches in length with a powder chamber would be a safer and stronger design.The sidewalls are too thin for the bore size.

I would go over to the below link and plow thru the posts and stickies on cannon design and building. I would also purchase a copy of Matt Switliks book:The Complete Cannoneer.


http://www.go2gbo.com/forums/index.php/board,88.0.html?PHPSESSID=8e90s79k5p8olegrha1c26o530

 

[brushhippie]

Thanks Rod, I had planned to cut the plates off and plug the end then another plate over, also to slide a pipe over the bottom and weld about a 6 inch peice to beef the chamber. I still really doubt Im gonna put any kind of heavy projectile in it anyway, but many thanks for the link and the advice.

 

[Pete D.]

Cannon

Golf balls are 1.680" diameter, but, I figure with a thick patch it should seal the bore pretty good.

No patch. These golf ball mortars and cannons do not use patches. The loose fit of the GB into the bore is done on purpose. It is called "windage" and it is supposed to be there.
GB mortar from a design by DD:


This last is the breechblock with its powder chamber. Notice the thickness of the sidewalls (plus the pipe itself):

 

[[email protected]]

I see a accident waiting to happen.

 

[zimmerstutzen]

Just my opinion, far too dangerous
I have and shoot cannons. Never ever anything with a welded breech and always a tube wall thickness equal to bore size

A guy over in gettysburg had a heavy pipe cannon that blew after its couple hundredth shot
He is sitting in the state hotel for involuntary manslaughter

 

[Rojelio]

No patch. These golf ball mortars and cannons do not use patches. The loose fit of the GB into the bore is done on purpose. It is called "windage" and it is supposed to be there.
GB mortar from a design by DD:


This last is the breechblock with its powder chamber. Notice the thickness of the sidewalls (plus the pipe itself):

--------------------------------------------------------------------------------

Quote:
Golf balls are 1.680" diameter, but, I figure with a thick patch it should seal the bore pretty good.

No patch. These golf ball mortars and cannons do not use patches. The loose fit of the GB into the bore is done on purpose. It is called "windage" and it is supposed to be there.
GB mortar from a design by DD:


This last is the breechblock with its powder chamber. Notice the thickness of the sidewalls (plus the pipe itself):

Thanks, Pete! I'm going to make a breechblock similar to DD's except threaded like an inline. I haven't decided on which ignition to use. Fuse would be the simplest, but, Dixie gun works sells a cap igniter you use with a long string. Still thinking about that. Also thanks again for the info on windage. How much windage is actually required?

 

[Pete D.]

Windage.

Windage. The bore on that GB mortar is 1.725". A Golf ball slides right down to the powder chamber.
It was made from DOM tubing.
Pete