Yes sir, I started there a week ago:
Golf Ball Coehorn, first post: No plans, photos missing or invalid links
Golf Ball Coehorn, second post: No plans, no photos.
Golf Ball Coehorn, third post: Promising link to a plan, but link is invalid, no photos.
Bowling Ball Morter, one post: No plans but some cool photos.
Soda Can Coehorn, one post: Invalid link to mortar plans in post 6
I did glean the following:
A golf ball gun with proper windage would need a minimum bore of 1.723 inch.
The diameter of a golf ball is 1.68 inch. . (1.68/39)x40=1.723
http://www.learnaboutgolf.com/beginner/balltypes.htmlA popcan mortar with proper windage needs a bore of 2.667.
A Diet Coke can is 2.6 inches in diameter. (2.6/39)x40=2.667
Bore size should be diameter of perspective projectile, divide diameter by 39, multiply result by 40.
Powder charge should not exceed 2 oz. of Fg or 3 oz. FFA or Cannon Grade Goex powder per inch of bore diameter. No excessive charges, use black powder only.