Longsmoke, That's a tough question. I use what I refer to as a weld/cast construction for all of my large barrels. I stack heavy walled high pressure pipe, one inside the other, with holes drilled in the sides, plug welded to maintain spacing. The breech plug is machined and cross pinned and welded on. The spaces between the stacked pipe are then filled with molten iron from my smelting furnace after the barrel skeleton is red hot, standing upright in a large fire. The exterior is then welded or ground to shape.
Im sure some will frown on my methods, but I have gone to great pains to try to blow one of the tubes up. I have never been able to create a failure using black powder. I've never tried to fail one with smokless powder.
Moose in Canoe, It's my understanding that the old timers almost always used 14 spokes and 7 fellows for this size wheel ( 36" ).
The accuracy is pretty good for a smooth bore. I've only shot at 100 yrds, so far, and hit a 4' x 4' target pretty regularly. I'm going to take it out to the farm soon and see what it'll do at longer ranges.
