cannon ball

[halfarod]

So i'm going to be firing a ball for the first time and was wondering how much wad would i use before seating the ball?

[Double D]

So i'm going to be firing a ball for the first time and was wondering how much wad would i use before seating the ball?

a lot more information needed? 

Type of gun, caliber, projectile type, type and quantity of powder.   

[halfarod]

well the bore is 3" and the balls are 2.875"... i'm not sure on the load, i've only fired blanks out of it at 1400 grains. so any information would be helpfull. i've been told to cut the load in half when shooting a ball, but do you use a wad too?

[cannonmn]

Exactly what kind of cannon do you have?  Don't take this to be sarcastic, but we need more info.  See we're kinda hesitant to spew out information that might or might not be good for your situation, we don't like to assume since like I was taught in the Navy, if you azz-u-me, it makes an azz out of u and me.  If you are shooting a potato cannon made out of PVC pipe, for instance, we're going to recommend a very light load.

[BoomLover]

Halfarod, I think what they are looking for is 1)..material barrel is made of, 2)...method of manufacture, machined, cast, welded, ect, 3) what do you want to shoot, steel, lead, Zinc balls, (all different weights, so, different powder charges) 4) what grade of powder.. cannon, Fg, FFg, FFFg, 4)..method of firing..(since it is your first projectile from this barrel, safety measures taken?) Posting  a pic or two of your barrel would be helpful, also. They don't want to be giving info that could be used wrong, or mis-understood, I think you would agree? Thanks, BoomLover

[brokenpole]

Halfarod, I think what they are looking for is 1)..material barrel is made of, 2)...method of manufacture, machined, cast, welded, ect, 3) what do you want to shoot, steel, lead, Zinc balls, (all different weights, so, different powder charges) 4) what grade of powder.. cannon, Fg, FFg, FFFg, 4)..method of firing..(since it is your first projectile from this barrel, safety measures taken?) Posting  a pic or two of your barrel would be helpful, also. They don't want to be giving info that could be used wrong, or mis-understood, I think you would agree? Thanks, BoomLover

This is precisely why I enjoy this board so much.  The folks here are knowledgable and are concerned about safety first and foremost.

I was part of another board once that did not follow these tenants and a couple of the members were killed when one of their backyard contraptions blew up on them.

Listen to these folks halfarod.  It may save your life and others.

Sorry...I feel strongly about safety as well.  May be some day I will relate my personal story.

[KABAR2]

Also depending on size of bore wading may not be advisable.... you may need a Sabot.

[halfarod]

Ok..all the parts were machined out of 4130. I'll be shooting lead with cannon grade powder. the breech is 7.5 and the chamber is drilled out to 1.5 so there is plenty of steel there. the bore is 3" I'll attach the picture of the building process so you guys have a better idea as to what i have. thanks you for all your help

[Double D]

Okay, now we have enough information. 

4130.  I see some welding.  I let those more knowledgeable talk about that.

It appears you have built a howitzer.  Your bore is 3 inch and your powder chamber is 1.5 inch.  That makes a big difference.

Your load will be based on the diameter of your powder chamber.  The diameter of your powder chamber is considered your bore.

First go to our sticky called Safe loads and cannon plans at the top of this forum.  You will find there a load chart from Switliks book the More Complete  Cannoneer that says Maximum safe load for a 1.5 inch bore is 500 grains of Cannon grade powder. If you use FG powder you can expect about a 40% increase in pressure.  Expect even more increase in pressure when you use even finer grades of powder.

Your projectile.  In a 3 inch bore the windage rule of thumb is 1/40th.  So 3/40 = 0.075 x 39= 2.925*.  You can use a ball of 2.925 diameter.  Your 2.875 ball is a little small but will work.    Your ball of lead will weigh right at 5 lbs.  A ball of Zinc will weigh about 3 pounds.  The two pound difference in weight is significant and you will have to compensate for the extra weight.  A ball of zinc will closely approximate the weight of an iron ball of that caliber.  The heavier ball will require lighter powder charges to keep pressure down.  The heavier ball will generate higher pressure with equal loads.

Another thing that heavier balls and charges will do is tear up your equipment with violent recoil.

Switliks says when developing starting loads start ridiculously low. For you gun with lead balls I would start with 100 grs of FG.  If you had Zinc balls I would still start with 100 grs of FG.

In the first post in the Safe Loads and Cannon plans you find a link called Making Cannon Cartridges.  Read it and make cartridges for your gun.


*  Yes I know I could subtract .075 from 3 and get the answer,  but 3/40 = 0.075 x 39= 2.925 is step by step on the calculator.