Author Topic: 'bout ready to blast a bowling ball  (Read 4680 times)

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Offline NitroSteel

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« on: May 28, 2004, 08:45:04 AM »
I've got all the pieces at the machine shop getting the boring, milling and welding done - - by a client/friend who is a certified welder.  

The main thing I was worried about was MY welding.  The fellow at the machine shop was so fascinated by the design that he is doing all of the machine work for very little - - I just gave him the bottom half of the proper size oxygen cylinder and a piece of 4" round stock so he can start on one of his own.

I picked up a 3 foot piece of steel I-Beam today from the junkyard.  It is about 1/2 inch thick and about 12 inches wide.  I'm planning on using it for my carriage - - I think it will be heavy and strong enough.

I think I'm going to just run a piece of fuse (taped into place) into the barrell along the side of the bowling ball and into the powder chamber.  It should fit just fine (my cylinder is 29-3/8 in circumference).  Other than the steel carriage and the fuse (instead of slap-hammer) this is going to be nearly identical to the "Original Florida Bowling Ball Mortar".

I'm planning on using FFg Black Rifle Powder for propellant.  How much should I use?

Do ya'll forsee any problems with this design?  Anything I should change before it's too late?

Thank ya'll for all the help.

Offline jimwaits

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« Reply #1 on: May 28, 2004, 10:50:09 AM »
Sounds like you going to town on that rig! I wish mine were half that fast.
Bill Tyrrell uses from 1500 to 1750 grains (4 ozs) BP in his Florida Bowling Ball Mortar. If I were you I would not start off with that big load but would sorta work up to it slowly while keeping a close eye on things.

If you are going to use fuse why don't you just drill a vent hole about the middle of the powder chamber just big enough for the fuse. Then you could use a piece of fuse about six inches long or less.
Jim Waits

Offline NitroSteel

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« Reply #2 on: May 28, 2004, 12:30:31 PM »
I wasn't sure about drilling a hole in the side.  I'm not an expert on these matters - I just thought that it would be better if there were no hole in the side.  I was also planning on getting WAAAYYYYY away from this thing before it went boom, so fuse length wasn't really an issue.

Should I drill it straight down or angle it?  Or does it matter?  It won't cause too much loss in pressure???

How much powder do you recommend for the initial blast?  I don't have a scale, will I be okay using volumetric measure (like a cup full) or do I need to be more exact on powder weight?

Sorry for all the questions, hopefully I'll be hearing a boom by next Wednesday, but most definetly by next weekend.

Thanks again.

Offline Cat Whisperer

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« Reply #3 on: May 28, 2004, 12:59:19 PM »
I would drill a hole through the THICKEST part of the steel to the powder chamber.  It won't loose much pressure for you.  You have a HUGE surface area on the bowling ball, and a little windage (clearance) and a small flash hole don't compare.

BUT, putting the fuse out past the bowling ball - I'd hate to have it go off prematurely!
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Offline jimwaits

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« Reply #4 on: May 28, 2004, 01:01:26 PM »
Heck, I am just an amateur like you are. We got two pros on here as moderators. I am sure they will jump in soon. I am sure the fuse hole will lose some pressure but it is negligible on cannons/mortars. I would drill it straight in to about the center of the powder chamber. Make it on the top side. I think volume measure would be okay but you need something known to start with like a 35mm film can. Weigh a level can full of your powder and you can go by that pretty close.

There are instructions in this forum about making aluminum foil cups to put your powder in. You should check up on them and always use a brass rod to punch a hole in the aluminum down through the vent hole to insert the fuse. Make the fuse hole pretty tight.
Jim Waits

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« Reply #5 on: May 29, 2004, 06:10:00 AM »
First let me say that 1500 to 1750 grains is way to much powder.  Use 1F, musket or Cannon grade black.  

Tell me what the diameter of your powder chamber is and I look up your load.

The guys shooting the 24 lb coehorns were using 230 to 240 grains to lobe their balls 100 yards.  That's where I would start.  I think you will get a lot more fun out the smaller load. You will be able to watch the ball all the way and keep it with in safe range.   Keep in mind Bill was shooting out into the water and he can where the balls were going.  

You can slowly work your load up from there extending your range.  Just keep in mind this is a gun and you are lobing a 16 lb projectile and you want to know where it is going land.

Also there is no problem with drilling a hole for your fuse that's how it was/is done.  the fuse hole should be just slightly larger than your fuse.


Take pictures.

Offline NitroSteel

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« Reply #6 on: May 29, 2004, 09:42:21 AM »
My powder chamber is 2-1/2 inches deep and 2 inches in diameter.  It is bored into a piece of 4 inch round stock that is 5 inches long.

Where I will be shooting it is not a problem as long as I don't blast it over about 3 miles :lol:  - - - and I don't think that will be a problem.  There is nothing around us but open fields and pine trees (uninhabited).  I want to be able to blast it about 400-500 yards (I have a clear view of about 600 yards).

I will take pictures of the mortar as soon as I get it back from the machine shop.  The powder I have is FFg black rifle powder - - that's all I have, it is very hard to find black powder around here, so this is what I'm gonna use until I run out unless it is just absolutely dangerous to use.

Please let me know how much I should use to start with and what the maximum amount is that I should use.  

Thanks again for your help.

Offline willysjeep134

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« Reply #7 on: May 31, 2004, 08:16:36 PM »
finer powder burns faster, and creates more pressure.  You might be surprised how much oomph a ffg load might have. For safety's sake I would probably start out with a way too weak load and build it up to the range I want. If you get really hooked on cannon shooting and decide to order like a case of powder, most large chain sporting goods stores might be able to tell you where to get real black powder. If they have a BP license they might be willing to order cases or mabey even cans of Fg or cannon grade powder.
If God wanted plastic stocks he would have made plastic trees.

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« Reply #8 on: June 01, 2004, 03:35:04 AM »
"The Complete Cannoneer" reports on pressure test done with various grades of powder and says never use finer than Fg in a cannon.

The rule of thumb for loads in cannon of 2 inch or greater bore diameter is 2 oz. per inch is MAXIMUM.  In the case of Howitzers and mortars, the bore diameter is the diameter of the powder chamber.

I would start with half.  In your case 2 inch powder chamber, 4 ozs is max, I would start with 2 ozs and see where the ball goes.

I can tell you from my own experience that if you  load maximum you won't get as big a thrill out of the 600 yard shoot as you will a 100 or 200 yard shot. When you launch the ball at high speed it moves out of sight just to  fast. you may not even see it hit...water the exception.  The shorter shot you can follow with your eye all the way to target.  You can see, hear and sometimes feel impact. But that said you have fire at least one long one.

Check out the sticky we posted at the top of this forum called Blackpowder and Cannon Shooting resources.  you will find a list of powder distributers, including one who will ship you a 5 lb shipment instead of 25.

Offline w a tyrrell

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« Reply #9 on: June 01, 2004, 10:20:52 AM »
Looking forward to seeing your pictures.  

I haven't had a chance to shoot mine again since the original posting.  When you go shooting be sure to have a stop watch or in some way be able to time the flight of ball.  You'll regret it if you don't.  

Starting with low loads is certainly the way to go.  My first shot was about 750 grains and then 1500 after that.  As others have suggested this is probably way too much powder.  It would be nice to establish some loads and ranges.

I really don't like fuses.  I don't want to be standing over one of these things with an open flame.  What do you do if having lit the fuse it doesn't go off?  The slap hammer doesn't take too much work and the large rifle primers seem to give reliable ignition.

Best Wishes,  Bill Tyrrell

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« Reply #10 on: June 01, 2004, 12:59:16 PM »
Bill,

I got to thinking after posting that I thought your charges were a little heavy that they aren't.

If I remember right the diameter of your powder chamber is 2 inch.  Following the 2 ozs per inch rule that means that a max charge for your mortar is 4 ozs.   Well guess what, 4 oz times 437.5 (number of grs in a oz) is 1750 grs. I stand corrected.

That's what I get for making an apples and oranges comparison to grs. and ozs.

Fuse or primer misfires is not going to be good.  I think the safety rules discuss the procedure.  I look it up.  Might make a good discussion topic.

I saw a cannon that habitually misfired on fuse.  The guy drilled the vent out next drill size larger and never had another problem.

Offline Cutnroll@aol.com

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« Reply #11 on: June 20, 2004, 09:06:12 PM »
Hello everybody !  Just found this sight through a link on 1919a4.com.
Well, I say when in doubt, dump a whole pound in there. Thats the best way to test them. We have been doing this for a couple of years, you can view some photos at SoCal50's. I'm the nut in the middle with my 15 year old daughter, Nicole. One guy tested his mortar with a pound of ffg and two bowling balls. I put a pound in mine, the yellow one with the flames, and the ball flew about 3/4 of a mile. I still have fuse fire in both of my mortars, have a slap hammer, just havn't installed it yet. We do find that 1/4 to 1/2 a pound does a fine job pushin that ball up there. Just depends on how much powder you want to go through. When I did the pound in my mortar, it did force the base plate (a truck roter) back about 5 feet and straightened out an eye bolt that I had the front leg and base chained together with. Not a good idea to be standing close. I also set a video camera at the base, pointed up and you can see the ball fly out and out of sight. Balls are reuseable if they don't land on a rock.  Got any ?? shoot me an E-Mail    BLAAAAAAAAAAAM                  JAN

Offline jimwaits

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« Reply #12 on: June 21, 2004, 04:00:53 AM »
Hello, boy that sure sounds like a lot of black powder!! I really would like to see those photos but that "SoCal50's" don't mean anything for me. Little more info please?
Jim Waits

Offline Cat Whisperer

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« Reply #13 on: June 21, 2004, 03:34:36 PM »
Quote from: [email]Cutnroll@aol.com[/email]
Hello everybody !  Just found this sight through a link on 1919a4.com.
Well, I say when in doubt, dump a whole pound in there.


I would hope you take the appropriate precautions of earthworks  of sufficient size to contain the explosion IF it were to go up in smoke.

Did you measure  the bore before and after the proof testing to see how much you stretched it out?

Having seen a cannon explode, while standing less than 15 feet from it, I take the safety issues VERY seriously.  Crossing the fine line of getting away with it or not, is too easy to do.  It would be interesting to KNOW how much powder it would take to over stress one of the bowling ball cannon/mortars.  

Just a word of precaution.  Keep it safe, have fun.

We have some sage words of saftey quoted from sevaral sources listed at the beginning of this forum.  Most of them learned the hard way.
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Offline Cutnroll@aol.com

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« Reply #14 on: June 21, 2004, 06:21:40 PM »
Jim & Tim
Hello Fellas.............I don't know whats up with the site SoCal50's . It may be case sensitive, or site down, Thats what I click to go to the site, with no .com either. Anyway, I will investigate and get back to you. In the mean time I do have 2 photos I can send you. E-mail me and will send in attached file.

 Cutnroll@aol.com


One photo is group picture, the other is the mortar line.

Jan

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Safty
« Reply #15 on: June 21, 2004, 06:27:39 PM »
Oh, yeah, about the safty thing, yes we are very safe. I drill a hole in the bowling ball between the 2 finger holes insert a string and lower the ball into the mortar.(So you don't have to stick your arm in there) One mortar is about 3 feet long and the other about 4 feet. ( you know, have to do that longer barrel more velocity, more distance thing)Also, I pour the powder in using a brass funnel as brass doesn't conduct static electricity. Have lots of video, just don't know how to put it on the puter.

Jan

Offline jimwaits

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« Reply #16 on: June 21, 2004, 06:47:42 PM »
I still need info on how to find that SoCal50's bit! You can't put the movies up here, not enough space. If you can find a place like Neptune.Com
which hosts space you can put the movies there. They offer a free 10 day trial which I used. Then I bought a 150megabyte piece for a year pretty
reasonable. I have some photos of my little golf ball mortar up there.
see.....   http://www.jimwaits.neptune.com   three files, some still shots
of construction on golf ball and bowling ball mortar and a movie with sound of the firing and one high speed movie showing ball in flight.
  You could put your movies up there for ten days free...
Please, again tell me how to find those SoCal shots?
Jim Waits

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« Reply #17 on: June 22, 2004, 08:18:22 PM »
Jim
hope you got the pictures ok. Thanks for the other info. I will have the info on the SoCal50's site probably tomorrow.
Jan

Offline Cutnroll@aol.com

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Mortar Pictures and a bunch of other guns 50's 30's etc
« Reply #18 on: June 23, 2004, 06:25:47 PM »
Gentlemen,
Ok here it is,

                 http://www.daplane.com/50bmg/ds2004/

This was our desert shoot that the 50 cal club has twice a year.
Lots of 50 cal, M2, 1919a4, and some pretty good shots of several of our homemade bowling ball mortars. Ya all should come out and try out some of our deep fried turkey.
Jan
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Offline jimwaits

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« Reply #19 on: June 24, 2004, 05:37:47 AM »
Thanks a million for the pictures. I really gobbled up those pretty shots!
Jim Waits

Offline Blaster

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« Reply #20 on: June 24, 2004, 06:29:18 AM »
Great job with some super pictures.  Many thanks!!  Blaster (Bob in CO)
Graduate of West Point (West Point, Iowa that is)

Offline Fred

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« Reply #21 on: June 24, 2004, 07:59:28 AM »
Thanks for the pic's.

The web-site pic's were great.

Thanks FRED................

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« Reply #22 on: June 24, 2004, 12:21:19 PM »
I looked at those pictures and I want to point something out.  None of those guns appear to be mortars.  They all appear to be high elevation Howitzers!

A black powder mortar has a barrel that is no more than twice the length of the projectile.

(obstacle blocking the river!) Why did I have to see that!!! Now I need two O2 tanks, one for a Mortar and one for a Howitzer!!!  :grin:

Offline Cat Whisperer

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« Reply #23 on: June 24, 2004, 04:06:31 PM »
On the other hand, DD, the 'definition' of what is a mortar and what is a howizter is often characterized by the trajectory.

MODERN mortars may well not fit the classic definition of mortar (length of bore being 2x that of bore diameter) but the trajectory is certainly high and short, compared to that of a howitzer or gun.

And, yes, two (or more) 02 tanks are needed for anyone's collection.
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Offline Cutnroll@aol.com

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« Reply #24 on: June 25, 2004, 08:44:37 PM »
Cat & DD

You guys are just tooooo technical for me. (I do like Howitzers though)
Believe it or not, I had thought about rewelding the peice that I cut off the end back on, only sideways to replicate a muzzle brake as the look of the Panzer tank. Crazy, huh ? My design of the longer mortar (or Howitzer if you prefer) was to replicate a big 50 cal barrel. I was going to drill holes in the end (the silver part) to have the look of a 50 bmg muzzle brake.
All the fella's I shoot with have 50's. I'm the only one that doesn't have one. All I know is they all work and its a blast. I tried glow in the dark paint on the balls, it didn't work, must have burnt off. A couple guys tied calume light sticks on a couple and that did work. We are working on a couple ideas for our next trip, a ball that has a timed fuse that blows up in the air, and a clear ball to have a bright light inside for night shots. I know, we have too much time on our hands !!!
Jan

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« Reply #25 on: June 26, 2004, 12:31:15 AM »
Our technical definition of howitzer vs mortar in this instance is Tongue in cheek technical.

If you need cylume and streamers to follow a bowling ball you are grossly over loaded.

If you want some real drama with you mortar increase you elevation and reduce your powder charge.  The ball will go more straight up and slower so it can be seen and it will hit closer to you.  Where we fired our beer can mortar the cans hit about 100 yards out and you could hear and feel the impact. It's a lot more fun when you can see the ball almost from the muzzle to impact


Get a 55 gallon drum and set it out at 100 yards and see if you can hit it. Better yet shoot into a pond or body of water....looks in short supply on you range.

Exploding bowling balls...don't do it, damn dangerous, and very illegal. You already have the spot light on you for shooting the 50 Cals...shooting exploding projectiles may bring some very unwanted heat on you.  Right now you are very loosely covered under the antique weapon rule...but if some petty ATF rookie wanted to create some serious heartburn for you he could question if your mortars are replicas...

Muzzle brakes.  Remember that  expanding gases are going out the side of brake.  Now you have an elevated barrel. You are moving the blast cone back towards the firing line. Can get a bit dicey.  You don't need it.  Especially if you use more reasonable charges.

The maximum charge for a 2 inch smooth bore is 4 ounces. In the Mortar or howitzer the bore is the diameter of the powder chamber.

Offline Cutnroll@aol.com

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Exploding balls & muzzle brakes
« Reply #26 on: June 26, 2004, 10:01:33 PM »
DD & Cat

The muzzle brake was just an idea, just for looks, but I'm not going to make one. I'm going to cut a foot off the black and silver one though, its too damn heavy to move around.
The legality of our mortars. Not sure what you are talking about the antique thing and replica's, but the people I have talked to said that they are perfectly legal as front loading black powder guns.Now, if they had a breach, that would be a different story.
Never used a streamer, that was someone else's post. I don't think I would put on a streamer or anything of the sort that could jam up inside the barrel (like wadding) That could cause a catastrophic malfunction.One of our guys used calume light sticks for spotting the ball at night. The Mojave desert is pitch black no city lights. The night shot was pretty impressive I might add.
The 50 cal guns are very much legal here in California. That could change by the time you finish reading this. If I put a spike bayonet on my Chinese SKS it becomes an illegal assault weapon. But UPS is delivering my 308 belt fed Browning 1919a4 on monday. I didn't see homemade mortars on the banned weapon list. We will probably have to register them in the future though. LOL
The exploding ball my friend was talking about making I believe he was going to put some fireworks inside the holes.
Usually we can see the ball fly out up and land, you can usually track the whole flight, unless someone packs a little too heavy powder charge.
I put a video camera on the ground next to the mortar and that made a pretty impressive video, you see the blast, the ball fly out and up curve to the left and out of range of the camera. Try that.

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« Reply #27 on: June 27, 2004, 01:14:25 AM »
If you vist our Blackpowder Mortar and Cannon shooting FAQ's you will see ATF's definition of Antigue Cannons.  They could be breech loading like a Whitworth rifle and be exempt as antique. It isn't just the muzzle loading part that makes them exempt its the age  or replica part that makes them exempt as antique.

If they were replicas of a design that was made after 1898 and were muzzleloading they are destructive devices.

That's why when I make my Guns I make them to look like the old guns. I don't want any gray areas.

I am interested in hearing how the Cyalume sticks were attached...that does sound interesting.

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« Reply #28 on: June 27, 2004, 10:33:35 AM »
DD
You mean they didn't have bowling ball mortars before 1898 ?? LOL
I will check out the FAQ's
We only do this twice a year, everyone is safe in what they are doing, the mortars (Howitzers) are tested, not too worried about the black helicopters swooping down on us. They want bigger fish to fry. As far as I know, everything out there is legal. (No Automatics) If our mortars (Howitzers) aren't legal, then neither are the golf ball mortars, can mortars, etc. I think , not sure, maybe each state may be different on this subject. (local laws ) Personally, I don't care. Its good clean safe fun.
The calume light sticks were attached by drilling a hole connecting the two finger holes. They were then cracked and wired on with copper wire I believe.
Jan

Offline NitroSteel

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It took a little longer than I thought
« Reply #29 on: October 13, 2004, 07:02:28 AM »
I finally got the completely welded up mortar back from the shop.  In the mean time I did find and buy 2 pounds of Fg black powder from a store who almost wanted to give it to me...  He said this was the last that he would have and that he was not going to renew his license for it.

At any rate, I am heading to the bowling alley shortly to pick up a few old balls and give it a shot this afternoon (hopefully).  After I shoot it I will take pictures and will give a report of the distance, results, etc.  I plan on cleaning it up and painting it later.

By the way, I did have a fuse hole drilled on top of the powder chamber and it actually comes out near the rear of the chamber (not the center as instructed), but the work was done for free and everything else is perfect.  I plan on being at least 100 yards away from this thing, and behind something substantial the first few times it goes BOOM!

I plan on using 2-3 ounces of Fg black powder (measured on my postage scale).  

Please let me know if I should not use this much powder or if something else should be done differently...