golf Ball Cannon

[acoop101]

I want to build a cannon that can shoot golf balls,  when you get to that size does the rule of thumb of the walls of the cannon being as thick as the bore meen that there I would need a pice of 5 inch diamiter steel to make this cannon? Also do people have a recomendation on powder charges, I have some FFFG pyrodex, or should I go and buy something with fewer F's I think the largest they sell around here (San Luis Obispo Ca) is FFG so any charge recomendations would be apriciated.
Thanks In Advace

[GGaskill]

Only the first few bore diameters at the breech end need to have the thick walls.  Look at a Parrott rifle or a Brooke.  You can build one that way.

Forget the Pyrodex.  It won't work worth a dam with golf balls as you can't get the pressure high enough to burn well.  While FFFg is not a good idea for anything over a half inch bore, a reduced charge would be safe if firing golf balls only.  But not with metallic shot; use Cannon grade if you fire metallic shot.

[Rickk]

You can mail order any grade of powder you want from Powder, Inc.

Maine Powder House should be checked out as well.

[Cat Whisperer]

If you add a powder chamber, then the breech end can be smaller - being 3x the diameter of the powder chamber, with adequate thickness behind the chamber and all internal 'corners' being rounded well (to lower stress risers).

[GGaskill]

One more thing so you can make an informed decision--CA law limits the amount of BP in "possession" to five pounds and only one pound in a vehicle.

Also, if you want to make a cannon, consider attending the cannon class at Lassen College this coming June.