Join Date: Jun 2005
Location: Okefenokee Swamp
Re: 2 1/8 Lapan's Foundry Cannon
Don't patch the projectile.
Smoothbore muzzle-loading cannon need windage. In this case "windage" refers to the clearance between bore and projectile and not the more modern definition of lateral sight adjustments.
Bores foul, projectiles can be imperfect or inconsistent. A little windage is necessary to avoid a high-pressure incident.
That said, I know of a couple of extreme cases where patching has been used. But in these cases it was very loosely patched, mainly to allow use of a grossly undersized projectile. It was not a tight seal, and in both cases these were mortars which are very low-pressure in comparison to a cannon.
Something you should do is have the bore diameter measured. A little knowledge of the gun's properties can go a long way in the future.
A ball gauge should also be built. This is a tube bored out to the diameter of the bore. The length of the gauge should be three times its diameter. All projectiles should be checked before loading. Oblong projectiles like cans should slide through easily, balls will roll in the bore so they should be made to roll through the gauge (out-of-round balls can sometimes be slid through, but won't roll through without jamming).
Any projectile that fails the gauge should be discarded. Better to find out now than when a can with a bent rim jams halfway down a loaded barrel.
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