First cannon

[Double D]

Mortars, especially golf ball mortar are not very impressive, but the can be a lot of fun...are you able to hit what you aimed at?   

Table spoons are for eating ice cream not measuring black powder, get yourself a black powder measure  and throw charges with that.  If you look at the Safe Loads and Construction sticky at the top of the board and you will find the formula for determining maximum loads.  Remember in a mortar the diameter of the powder chamber is the diameter you use to determine  the load.

Quite simply the newspaper can a will increase pressure and maybe even dangerously.   Newspaper also burns and can start fires.  If you use newspaper as a wad it becomes a projectile a flaming projectile and a litter mess. 

Absolutely swab and dry the bore between every shot. It's part of the safety procedure. That fouling can hold sparks and blow when you dump powder in. 

Here are National Safety Rules and Procedures
For Shooting Muzzleloading Artillery .  These are for large bore guns as well as small guns lik eyour.

For blanks you can cut a snug bore size piece of cardboard and put it over the powder chamber.  But watch it,  that also it can smolder and start fires.

Check the cannon classified for the group buy steel golf balls.  If you shoot them reduce your starting load and work up.
 

[GGaskill]

Golf balls are so low mass that they don't give enough resistance to the powder for the pressure to stay high enough for a good boom.  Try shooting the Fox "golf balls" for more boom.  But make sure you are in a place where that is safe.  A steel Dictator should be safe with any reasonable load.  Just stay reasonable.

[keithinvestigations]

Great thanks guys.

[keithinvestigations]

Almost 60 days later, I finally get my Hearn Coehorn.  Sheesh, they are slower than Christmas, literally.  Good thing I wasn't in a hurry, lol.  I'm taking the barrel down to my machinist to drill the vent hole and liner.  I use 1/8" green fuse.  From what I have learned here, I'm going to instruct him to do the following:

1.   Drill vent liner through dimple on outside and thread for 9/16ths grade five stainless steel bolt.  The hole in the bore should be .400” from face of breech of the bore. 

The hole may be angled so that it is .400” from the face of the breech of the bore.  To drill the hole, the machine shop may use a piece of round stock that fit the bore snugly to hold the barrel. By trial and error, set the bar up so that the drill hits the center of the vent dimple when the barrel is slid over it until it bottoms out, and so that, with the barrel removed, it hits a point .400 from the end of the round stock.

2.   Center drill the bolt with a 5/32nds bit.  Remove head from bolt and cut a slot for a screw driver so that the bolt may be removed.  Ground the bolt at the tip to roughly match the tip profile of the 9/16ths bit.

How does that sound?

[Double D]

What diameter are you making in the vent liner for fuse?

[keithinvestigations]

Drilling it with 5/32cd drill which would be .16".  Using 1/8" fuse which measures to .13".