Slake said:What about thickness of the block itself or is that elementary, compared to calibre? It seeems to me something you would do just before a shoot, not, say weeks?
There are variables you can work with (or around), for instants, if the wood is thinner than the diameter of the roundball, the patched ball will protrude out the bottom of the block when properly loaded, this could serve as an alignment guide to the muzzle, down side is that the lube could get rubbed off of the exposed part...
Thicker wood offer another option, after drilling the holes for the roundballs, flip it over and counter-bore it a little with a wood bit the size of your barrel, this "step" will work as a centering guide as well...
The grain and type of wood also matter, soft wood will break easier than hardwoods, watch the way the wood's grain pattern runs, it could create a weak spot and snap when the block is used...
I would more than likely make mine from a semi-hardwood like sassafras, if'n I still had some... :grin: