Author Topic: Need help (Read 2170 times)

dynomike1 · « **on:** April 12, 2008, 01:45:01 PM »

I just got me a mountain howetzer barrel. Can some one tell me where i can get a ball mold made? i am not haveing much luck on the links. I will probabley need powder and primers to. The bore looks to be 2.25" altough i havent put a caliper in it yet. I am also new at this. Any help would be appreciated.

Double D · « **Reply #1 on:** April 12, 2008, 02:30:17 PM »

Did you send an email to our sponsers and ask them if they can make you a ball mould. By the way the Mt. Howitzer is larger than 2.25 inches.

dynomike1 · « **Reply #2 on:** April 12, 2008, 03:01:14 PM »

Nope it's a 3/4 replica i guess.

Terry C. · « **Reply #3 on:** April 12, 2008, 03:32:16 PM »

Quote from: dynomike1 on April 12, 2008, 03:01:14 PM

Nope it's a 3/4 replica i guess.

Not necessarily.

Many makers underbore their replica guns (especially cast barrels). Hern for example, makes a full-scale Mountain Howitzer with a 2¼" bore.

Do you know who made yours?

dynomike1 · « **Reply #4 on:** April 13, 2008, 04:12:47 AM »

It's like 37.5 X 7. I haven't mic-ed the bore yet. No markings. When i strip it down to re paint it i will re check.

Terry C. · « **Reply #5 on:** April 13, 2008, 04:49:44 AM »

I went back and looked at the ad for the Hern barrel again. It lists an overall length of 37¼".

I'm of the mind that this is a full scale replica, with a bore of 2¼".

2¼" is a frequently used generic bore among replicas, but you will still need to know the exact diameter before you order a mold. Be sure to allow for proper windage. 39/40 is the commonly accepted standard.

Unless you plan on competing with it, this is actually a good thing. Safety-wise, the smaller bore diameter and resulting increase in wall thickness, should yield added strength.

The lighter projectile and reduced charge, along with the increase in mass, will shift the power-to-weight ration in favor of a more controllable gun.

I want one!!!

dynomike1 · « **Reply #6 on:** April 13, 2008, 05:00:47 AM »

I am not exactly sure what you mean by 39/40 windage.

Terry C. · « **Reply #7 on:** April 13, 2008, 05:55:44 AM »

The projectile should be 39/40 of the bore.

Determine the bore diameter, divide that by 40, then multiply by 39.

The result will be 39/40 bore diameter, this is your desired projectile diameter.

Let's say as an example, that your bore is a perfect 2.25" (it probably isn't, so check first).

2.25 ÷ 40 = 0.05625
0.05625 x 39 = 2.19375

2.19375" is your nominal projectile diameter. This should be held as close as normal machining and casting practices will allow.

It can work in reverse as well, if you have a specific projectile that you want to design a gun around.

Take the projectile diameter, divide by 39, then multiply by 40.

The result will be your desired bore diameter.

dynomike1 · « **Reply #8 on:** April 13, 2008, 06:59:23 AM »

I got you. what will be tight enough for competition? Without a digital caliper i came up with 2.343 or 2.375.

Terry C. · « **Reply #9 on:** April 13, 2008, 12:07:40 PM »

My comment about competition was aimed (pun) at the fact that at least some of the major organizations will allow only exact replicas with full-scale bores.

I'm not a competitor, so I can't really provide any more help there. Maybe one or more of the competition shooters can offer up some additional info on the rules of various organizations.

Quote

what will be tight enough

Windage is by definition, looseness. Tight is bad, tight is to be avoided in smoothbores. Loading and firing a smoothbore requires a certain amount of clearance between ball and bore.

Too little, and the projectile could be hard to load in a fouled bore, increasing pressures beyond safe limits. Worse yet, a ball could jam in the bore, creating a dangerous situation.

Too much, and you get excessive gas escaping around the ball, causing loss of velocity.

That's the reasoning behind the standardized formula of 39/40.

The above only applies to smoothbores. Rifled guns are a whole 'nuther animal.

Artilleryman · « **Reply #10 on:** April 13, 2008, 12:31:17 PM »

I do a little competitive shooting with both smoothbore, rifle, and mortar. In the N-SSA the requirement for windage is to have a tube gage the same diameter as your bore (usually from the same piece the liner was made from) that you can roll your projectile through. This gage should be at least two and half calibers long. For rifled projectiles the round should be able to slide through the gage. The closer fitting projectiles should be more accurate. Just don't make them so close fitting that they hang up in the bore. I would rather be less accurate that have that happen.

dynomike1 · « **Reply #11 on:** April 13, 2008, 01:18:50 PM »

I guess 39/40 is my best bet for now. I may change later on. I really appreciate the help from ya'll. Now i got to find somewhere to get me a mold made. I sent Seacoast an e-mail and Tyee Tackle Shop

GGaskill · « **Reply #12 on:** April 13, 2008, 04:12:46 PM »

Since you can't measure deeper than the muzzle with a caliper, you should make a gauge in the general shape of a rammer. Run it down the length of the bore to see if there are any tight spots. Each time you are able to go the whole length of the bore without sticking, put a layer of plastic electrical tape around the plug to increase the diameter and try again until you encounter resistance. That will give you a better idea of the minimum bore diameter in case it is not at the muzzle.

Double D · « **Reply #13 on:** April 13, 2008, 06:08:17 PM »

Did you contact each of our sponsors and ask them if they would make you a round ball mould. Ask them first they pay for this board. My first suggestion would be Kap Pullen.

http://www.gboreloaded.com/forums/index.php/topic,108723.0.html

dynomike1 · « **Reply #14 on:** April 14, 2008, 02:22:15 PM »

Sent Seacoast and Tyee one yesterday and Ken just now. Havent heard from seacoast yet. I will look for a rammer tomorrow. Thanks

Ex 49'er · « **Reply #15 on:** April 14, 2008, 02:37:45 PM »

Try Dom Carpenter for the rammer. He made a worm for me and I am very happy with it.

seacoastartillery · « **Reply #16 on:** April 14, 2008, 02:50:04 PM »

We don't make them, but we sent you a reply within 10 minutes of getting your enquiry yesterday, we just re-sent it in case it didn't go thru the first time. Check your email or simply look in the 9th sticky down from the top of this board called, "Where to find black powder cannons and shooting supplies" then look under "ball molds". Good luck!

Regards, M & T

dynomike1 · « **Reply #17 on:** April 16, 2008, 04:36:06 PM »

Thanks. I have been working 16 hrs. a day. I didn't even think to look there.

Cat Whisperer · « **Reply #18 on:** April 17, 2008, 12:49:33 PM »

Quote from: dynomike1 on April 16, 2008, 04:36:06 PM

Thanks. I have been working 16 hrs. a day. I didn't even think to look there.

So what do you do in your FREE time?

16's take a toll ....

dynomike1 · « **Reply #19 on:** April 19, 2008, 03:55:50 AM »

The only free time i have is July, Aug., Sept. and 1/2 day Sundays. Not much hunting and fishing anymore. When it rains i try to work on some of this stuff at work, then all i have is a mig, torch, and vise.I finally got my caliper my bore is 2.361 seems to be straight all the way through. I found a little resistance about 8" to 10" in. Just enough to feel it.

Double D · « **Reply #20 on:** April 19, 2008, 07:19:06 AM »

Quote from: dynomike1 on April 19, 2008, 03:55:50 AM

I finally got my caliper my bore is 2.361 seems to be straight all the way through. I found a little resistance about 8" to 10" in. Just enough to feel it.

Little bells going off in my head, Who Made this barrel?

dynomike1 · « **Reply #21 on:** April 19, 2008, 09:43:46 AM »

Have no idea. Somebody up north.

Double D · « **Reply #22 on:** April 19, 2008, 03:48:15 PM »

Can you describe the construction of this cannon tube?

Is it cast with a liner?

dynomike1 · « **Reply #23 on:** April 20, 2008, 05:08:01 AM »

Bore 2.361" after honing
Lenth 37.5"
Trunion 2.73x2"
Widest part of barrel 7.5"
Narrow part of barrel 6"
W/ steel sleeve

Double D · « **Reply #24 on:** April 20, 2008, 05:59:52 AM »

Is the liner seamless?

dynomike1 · « **Reply #25 on:** April 20, 2008, 06:31:11 AM »

Yep seamless.

Double D · « **Reply #26 on:** April 20, 2008, 08:19:04 AM »

That a big plus.

dynomike1 · « **Reply #27 on:** April 21, 2008, 03:01:44 PM »

Is copper an option for cannon balls? I think i can get it free.

Cat Whisperer · « **Reply #28 on:** April 21, 2008, 03:59:44 PM »

Copper is about the right density - how to form it is the problem.

I've got about 50 or 100 lbs of 'bricks' of copper - it would have to be right-much hot to cast. I'll likely trade it for something more directly usefull.

GGaskill · « **Reply #29 on:** April 21, 2008, 04:27:52 PM »

The price of copper has gone way up recently. I'll bet you could trade it for two or three times as much zinc (maybe more) which would be more easily melted and about the same density.