Author Topic: new cannon/mortar (Read 2695 times)

Bornsouthern34 · « **on:** April 28, 2009, 04:25:31 PM »

Victor, I think I have caught the bug. This is my new project.

GGaskill · « **Reply #1 on:** April 28, 2009, 09:17:30 PM »

I am looking for the collection of old bowling balls in the background.

Victor3 · « **Reply #2 on:** April 29, 2009, 02:05:41 AM »

Quote from: Bornsouthern34 on April 28, 2009, 04:25:31 PM

Victor, I think I have caught the bug. This is my new project.

You sure did get bored with them golf balls quick!

Double D · « **Reply #3 on:** April 29, 2009, 04:08:01 AM »

You carriage looks to small and unstable with the angle of the barrel. Wheel won't help. If you search the board for Bill Tyrrell's Floridia bowling ball mortar. He had a similiar configuration for the base and his mortar would flip on its back.

Cat Whisperer · « **Reply #4 on:** April 29, 2009, 06:54:52 AM »

Looks big enough so that you could clear out all the junk in the shop by loading into it with two or three shots.

GGaskill · « **Reply #5 on:** April 29, 2009, 12:25:15 PM »

Your carriage looks too small and unstable with the angle of the barrel. Wheels won't help.

I had similar thoughts when I first viewed this piece. The wheels are an interesting variation. It is my opinion that if fired on a smooth hard surface, the wheels will prevent the piece from falling over backwards because there will be no force that can be applied to the bottom of the carriage that would form a couple. However, if the wheels are not free to roll, the axis of the bore appears to be behind the axis of the axle which might cause the piece to flip over. One way to fix this is to make the barrel closer to vertical or tip it over and face it the other direction.

Bornsouthern34 · « **Reply #6 on:** April 29, 2009, 12:32:09 PM »

It is still under construction. I plan to take 6 to 8 inches off the barrel length. I just put it on to get a feel for how it was going to look. It has a long way to go before I can fire it. Until then, I am still content shooting golf balls. Nitrosteel has managed over 700 yards with his. He shoots from one end of the farm to the other.

I also buy every bowling ball I can find at yard sales. Funny how you never really pay attention to how many of those things are for sale until you start looking for them.

Bornsouthern34 · « **Reply #7 on:** April 29, 2009, 12:34:11 PM »

"Looks big enough so that you could clear out all the junk in the shop by loading into it with two or three shots."

My wife says I never finish one project before starting another. I guess by looking at the picture, she is right.

Double D · « **Reply #8 on:** April 29, 2009, 12:53:25 PM »

Rule of thumb length for mortar Barrel length shall not exceed 2 times the projectile length, while projectile length shall not exceed 3 times the bore diameter.

The chamber walls should be no lees than the diameter of the chamber in a mortar.

George could be right about the wheels working to prevent rear tip. I think recoil impluse will be to fast for the wheel to compensate. The rear extension need to be longer.

I know people who drive around the countryside stopping at bowling alleys and ask if they have any give way balls?

Nitrosteel is shooting golf balls 700 yards? How close is he coming to the target?

1Southpaw · « **Reply #9 on:** April 29, 2009, 03:03:08 PM »

And it works !

asking if they have any balls , that is ....

also any old pins ...makes a nice set up down range ... set up 10 old pins for a BB Mortar target

Still pondering base for mortar . I have some 1/4" wall 2x5 tubing . May cut into that I was going to use salvage angle iron but the tube and trunion are looking too good to make a junky base.
More to ponder ... am looking for more pictures of other projects . Want something that looks nice , and is funtional . (old art /pottery saying , "form follows funtion" )

I like the idea of wheels , or I'm needing a crane to move the darn thing . Perhaps a self propelled unit , powered by a BS (Briggs & Stratton ) or just plain BS powered

.
May be like moving a piano to an upstairs apartment , you find out who your friends are in a hurry .

1Southpaw · « **Reply #10 on:** April 29, 2009, 03:21:32 PM »

Bornsouthern34
Is that base a huge I beam ? Looks stout .
What do you have for powder chamber ?
How are the trunions fastened to the base ?
Elevation mechanism ?
I'm foundering my way through a project. Wife says my shop needs a clean up , I did sweep the floor .

Double D · « **Reply #11 on:** April 29, 2009, 03:45:09 PM »

If you guys go to the sticky at the top of the forum for safe loads and cannon plans an look over the list of Mortar links there you will find some base ideas.

You can also search the board for golf ball, soda can, pop can, beer can and bowling ball mortars. Lots of Ideas there.

I would also suggest you take a look at the sticky GBO Sponsors & Internet Blackpowder Cannons related links. Visit the websites there to get more Ideas.

Bornsouthern34 · « **Reply #12 on:** April 30, 2009, 04:44:25 PM »

Quote from: 1Southpaw on April 29, 2009, 03:21:32 PM

Bornsouthern34
Is that base a huge I beam ? Looks stout .
What do you have for powder chamber ?
How are the trunions fastened to the base ?
Elevation mechanism ?
I'm foundering my way through a project. Wife says my shop needs a clean up , I did sweep the floor .

Yes, it is a section of 12" I-beam. Very stout. Powder chamber is 4" round stock with the trunion welded to the base of the powder chamber. Looks bad because I left it in the rain in the back of my truck for about 3 weeks. Bad on me. Anyway, it will look better when I get it cleaned up and painted. As for elevation, none yet. I figured on adjusting the powder charge only but if any of you have any better suggestions please comment.

Double D,
After I cut 6 inches off the barrel, it will be exactly 2 times the length of a bowling ball and end precisely at the front of the carriage. Thoughts?

Bornsouthern34 · « **Reply #13 on:** April 30, 2009, 04:56:41 PM »

My bad, the I beam is 10". Also, the wheels are from 1000 lb casters off a big rolling tool box.

Again, it is still a work in progress. I will not permanantly mount the barrel until I get it cut down to a more appropriate size. My friend is getting 600 to 700 yards with a bowling ball out of his and they are almost identical.

GGaskill · « **Reply #14 on:** April 30, 2009, 06:33:13 PM »

After I cut 6 inches off the barrel, it will be exactly 2 times the length of a bowling ball and end precisely at the front of the carriage. Thoughts?

At that point you may be able to flop the barrel over the opposite direction and eliminate the stability problem. Do you plan to put some kind of "capsquares" above the trunnion?

Cat Whisperer · « **Reply #15 on:** May 01, 2009, 09:53:12 AM »

Quote from: Bornsouthern34 on April 30, 2009, 04:44:25 PM

...
After I cut 6 inches off the barrel, it will be exactly 2 times the length of a bowling ball and end precisely at the front of the carriage. Thoughts?

Longer bbl = greater range with same powder. But who has a place to shoot over 100 or so yards? A bowling ball coming down SOMEWHERE in the national forrest is scary to say the least.

Bornsouthern34 · « **Reply #16 on:** May 01, 2009, 07:04:55 PM »

I have not capped the trunion yet because I need to cut the barrel. I am still in limbo on whether or not to try and put some type of screw for elevation. As for shooting, we launch across a 100+ acre cattle farm. We also have permission to be on the adjacent wooded property if necessary.

Victor3 · « **Reply #17 on:** May 01, 2009, 08:38:33 PM »

A bowling ball coming down SOMEWHERE in the national forrest is scary to say the least.

If a bowling ball falls in the forest with nobody there to hear it, does it make a sound?

Bornsouthern34 · « **Reply #18 on:** May 02, 2009, 07:37:07 AM »

Only when it hits a tree.

carronader · « **Reply #19 on:** May 02, 2009, 09:09:18 AM »

you are all mad,and I used to work in magazines storing penta-erythritol-tetra-nitrate........that's the white powder in detonating cord (Cordtex) 1000lbs to a magazine even I wouldn't fire that Bornsouthern.

ps. they made a boom lover the safety rep...........me!

Double D · « **Reply #20 on:** May 02, 2009, 10:41:18 AM »

Bornsouthern,

What are the dimensions of the powder chamber?

Carronader the only part of his gun that holds powder is the little tiny chamber down in the bottom. The bowling ball sits on top of it. the larger visable barrel is little more than an expansion chamber and projector barrel for ball.

Bornsouthern34 · « **Reply #21 on:** May 02, 2009, 04:19:22 PM »

Powder chamber is cut from 4" round stock that is 6" long. As you can see though, the diameter of the chamber is 2" with a 1" wall thickness which is more than the recomended 1" to 1" rule. With that in mind, I do not plan on ever shooting it with a full load of powder.

Double D · « **Reply #22 on:** May 02, 2009, 04:25:09 PM »

No the wall thicknes rule of thumb is the wall should be the same thickens as the diameter of the bore. Bore in a mortar being the powder chamber. If you have a two inch diameter powder chamber you need the walls to be 2 inch thick also. 2 inch chamber your minimum safe recommended diameter would be 6 inches.

If your chamber is 6 inches long then that means with a 2 inch chamber the depth of you chamber is 4 inches.

Bornsouthern34 · « **Reply #23 on:** May 02, 2009, 04:31:09 PM »

Quote from: carronader on May 02, 2009, 09:09:18 AM

you are all mad,and I used to work in magazines storing penta-erythritol-tetra-nitrate........that's the white powder in detonating cord (Cordtex) 1000lbs to a magazine even I wouldn't fire that Bornsouthern.

ps. they made a boom lover the safety rep...........me!

"What if I told you insane was working fifty hours a week in some office for fifty years at the end of which they tell you to piss off; ending up in some retirement village hoping to die before suffering the indignity of trying to make it to the toilet on time? Wouldn't you consider that to be insane?"

Garland Greene, Con Air (1997)

I don't think we are all mad. LOL. Quite the contrary, I believe there is a very distinct difference between someone who understands and respects the destructive ability of explosives and the crazy fool you see on YouTube filling a pvc pipe potato gun with acetalyne. That is madness. Better yet, how about the fool that lets his friend shoot him with it.

Bornsouthern34 · « **Reply #24 on:** May 02, 2009, 04:38:15 PM »

Double D,
I think we are on the same page. I just read backwards sometimes.

Yes, it was my understanding as you wrote it, for some reason I am unable to convey that correctly. On mine I have a 1" wall with 2" bore. It should be 2" walls because of a 2" bore.

A test fire last night showed that I am going to have to use real BP or convert to percussion cap instead of fuse. Triple seven did not shoot good at all. We got 500+ yards out of Nitrosteels but he uses a 209 primer for ignition.

My dad said they used to put a very small amount of FFFF in the fuse hole to help with ignition. Thoughts?

Double D · « **Reply #25 on:** May 02, 2009, 05:03:38 PM »

No we aren't on the same page. Bore 2 inch, wall 2 inch all the way around the bore. Diameter is wall plus bore plus wall. 2 inch wall plus 2 inch bore plus 2 inch equal 6 inch diameter.

FFFFG will work, but you might want to take alook at the post on making quill. Much more efficient, and fun.

carronader · « **Reply #26 on:** May 03, 2009, 05:58:28 AM »

Glad to see you took my comment with a smile B,you know the informal meaning of mad is..........great energy,enthusiasm and you do have that.Why do you think I hang out in here ? like minds B. like minds.
If I hung out with you I would be a pain in the butt......'you sure you don't want to run another weld round there'..........'.you sure that'll be strong enough to support that'..........get the picture? I don't have DD's tact,diplomacy and patience (yes a compliment Douglas) I just jump in,I do risk assessment and quality control in Construction now,so I'm a bit regulated now.I remember telling my brother when we were kids to put a little roll of newspaper in the end of the pipe before we hammered it shut ;)putting Iso-propyl-nitrate in my car to see if it would go faster(pre-heat for early jet engines)building an express duck pond,maybe with the restrictions in UK I'm a bit too wary of repercussions.
You must know your capital hill is just busting with legislators ready to take any property damage or personal injury forward with all the media tools they got to promote control and restrictions.That's one reason I recognize the value of people like DD.(tetchy though he is)

Bornsouthern34 · « **Reply #27 on:** May 03, 2009, 02:20:58 PM »

Big Bangs are in my blood. As for the welds, they are stair stepped out from the chamber. Just a conservative guess, but I would say 3 high by 3 or 4 wide with good penetration.

As I progress with the mortar this week, I will post more pics. The wife says we are not heading out of town for Mother's Day so that means Saturday is a free day. Hint, Hint, I will be launching projectiles.

If anyone is interested, I will try to have another post soon of a 2000 lb Mobile Launch Rocket . I was fortunate enough to get to watch EOD detonate a damaged unit using 200 lbs of C4. By far my best experience with explosives.

Cat Whisperer · « **Reply #28 on:** May 03, 2009, 03:02:09 PM »

I ASSUME that the 4130 was preheated before welding to the recommended temp.

Cat Whisperer · « **Reply #29 on:** May 03, 2009, 03:06:22 PM »

Quote from: Bornsouthern34 on May 02, 2009, 04:31:09 PM

Quote from: carronader on May 02, 2009, 09:09:18 AM
you are all mad,and I used to work in magazines storing penta-erythritol-tetra-nitrate........that's the white powder in detonating cord (Cordtex) 1000lbs to a magazine even I wouldn't fire that Bornsouthern.

ps. they made a boom lover the safety rep...........me!

"What if I told you insane was working fifty hours a week in some office for fifty years at the end of which they tell you to piss off; ending up in some retirement village hoping to die before suffering the indignity of trying to make it to the toilet on time? Wouldn't you consider that to be insane?"

Garland Greene, Con Air (1997)

I don't think we are all mad. LOL. Quite the contrary, I believe there is a very distinct difference between someone who understands and respects the destructive ability of explosives and the crazy fool you see on YouTube filling a pvc pipe potato gun with acetalyne. That is madness. Better yet, how about the fool that lets his friend shoot him with it.

Acetylene is much more dangerous in that it is SO UNSTABLE that it can detonate (not explode) under the right conditions. Well off topic, but some great stories (considering we all survived).