Touch hole size?

[shortstart]

Hi folks,
I am currently building my first cannon. The tube is being made from gas well pipe. Approx. 1/2" wall, 12700 lb. tested. A golf ball fits well with minimal wind age. Planning on shooting blanks only! What would be the correct size for the touch hole and what would be a proper charge of cannon powder. Tube length is 24". The breech will have an exterior sleeve and the trunnions will be on another sleeve welded to the barrel. Thanks in advance.

 

[Poor Private]

What you could do, is what I did. I have a 24" cannon thats 1" bore. I ordered from Dixie a slap hammer around 30 bucks. drilled out the touch hole and tapped it and installed a musket nipple. you load the gun, prick the charge, install a musket cap and pull the string and bang it goes. Missfires are a lot less, and safer in my opinion than a fuse. If a fuse sputters and goes out, do you lean over it to check, or wait a couple minutes just in case it goes off? Do you prick the charge again and thread down another fuse and risk getting the back blast in your hand or face from a delayed firing. Nah I went with the slap hammer. You stand back and pull a string it pivots around and slaps down in the musket cap and bang.
Oh I just looked up the slap hammer, they call is a "cannon lock":
Page 347 of the 2015 Dixie catalog. p/n ACO606 $23.95, and listed right below it is the musket cap NP1335 5/16 x 24 $5.25.

 

[shortstart]

Thanks for the reply. I think the idea of the lock is the way to go. As to the charge, I was thinking around 2 ounces. Thanks again.

 

[Rifleman1776]

Most cannon fuse is 3/32". A 1/8" hole is just fine. I have never had a dud and don't see that as a problem. Putting a lock on a cannon just seems wrong to me. :td:
Start with lighter charges and increase until the boom you get is satisfactory to you. With blanks there is very minimal safety risk involved even with heavy charges.
Enjoy.

 

[Poor Private]

1/8" hole is to small. been there done that, on my other cannons had to drill out. during the civil war they didin't use fuse they used friction primers or cannon locks. fuse is too unsafe.

 

[shortstart]

Again, thanks for the replys. I have to wonder why fuse is less safe than a lock. It seems that fuse will allow you to step away from the cannon during firing.
One more question. What is the best material for packaging a powder charge? I have seen tin foil used. I'm a little short on silk bags right now and loose powder doesn't seem like a great idea. Thanks again in advance.

 

[Poor Private]

tin foil/aluminum foil is what is required in civil war reenactments.

 

[Rifleman1776]

1/8" hole is to small. been there done that, on my other cannons had to drill out. during the civil war they didin't use fuse they used friction primers or cannon locks. fuse is too unsafe.

The OP said nothing about reenactments, CW or otherwise. 1/8" accepts the fuse, can't be too small. How is fuse unsafe? It allows the shooter to back away. Works fine for me but if you can show where it is unsafe, I'll consider changing methods.

 

[Poor Private]

Unsafe because if it missfires (sputters and dies in the channel), you don't know if it is still viable or not. You have to wait several minutes before inspection of the gun.
By inspection I mean you can't lean over it and look in the touch-hole to see if it is still lit, you can't put a prick down the touch hole to see if you forgot to prick the charge(may still be an ember). Remeber your going to get part of the charge up out of the touchhole when it fires. You can't ram because of the same reason- nothing like seeing a ram and a couple of fingers go down range( I have seen it). Safety first. use a friction primer or a slap hammer is my choice on the larger tubes.
And yes I have 3 or 4 smaller cannons than the 2 1" bores that I have, and a mortar that use fuse, all the way down to fire cracker fuse. And I find that a slap hammer you can stand as far away as you want since your using a string.

 

[shortstart]

Replies greatly appreciated. The point is well taken as to lock versus fuse. I think I shall go with the lock. I am not interested with being historically correct in this particular instance. Safety first as this will only be used to get the neighbors attention. I really appreciate all of the responses. Thanks!

 

[Scota4570]

For my Cohorn mortar, I made a lock that cams a hammer over the top of a flat spring. A long string attaches to the hammer to start it moving until the spring takes over and slams it home. The string comes off the hammer as is falls.

I have used musket cap nipples, they work fine. Right now I am using up a bunch of old useless #57 shot shell primers in it. I made a "nipple" that takes the shot shell primer and added a little nub of a firing pin to the hammer. Never had a misfire with them.

I make my fuse holes so that the fuse fits in the hole easily but without unnecessary slop. There is something to the excitement and anticipation of not knowing exactly when it will fire.

Folks enjoy pulling the lanyard too. Take your pick.

 

[shortstart]

Thanks for the imput. All ideas welcome. The barrel is still a work in progress, but lookin good so far. I'm looking for plans on a naval carriage. Does anybody know where to find out the length of a 12# gun barrel? Then I can scale the carriage dimensions from that. Thanks to all