I have a black powder cartridge rifle in production. It's my first.
I'm studying loading both black powder and smokeless. My rifle will be a 45-70.
Cautions abound to not leave any air gap above the wad(s) with black, and to not use any wads with smokeless.
This is to avoid 'ringed' chambers. The mechanism most cited for this when it occurs is the bullet acting as an obstruction while air in the case is compressed to a very high pressure causing the ring.
The fellow who runs Shiloh Rifle has on his website a photo of a barrel sawed in half lengthwise that reveals TWO chamber rings, one where the base of a 405gr bullet would be, and one at the base of a 500gr. There is thus no doubt that this does occur.
Since the volume of air in the cushion section of a plastic shotgun wad is so large, the question I have is why does not a shotgun exhibit this phenomenon?
