You could re-matte the shine off that muzzle with a piece of fine Scotch-Brite pad. I would want at least a slight crown. A small grinding ball will work to do that (maybe a 3/4" diameter). I also used a small cone-shaped grinder to get just a bit more depth. You can then smooth it out with some JB patches under the ball... if you like.

Some of those groups you shot look like they want to break your 1" goal.