by Siringo » Mon Dec 01, 2014 9:36 am
Keep in mind, that when the bullet passes over the gas port, hot gasses escape under significant localized pressure, blowing past the bullet base at the port location, at a velocity that far exceeds the speed of the bullet. That hot gas escaping past the bullet base will cut a divot in the base of the bullet.
I had previously tried to use a 45 caliber sabot (for in-line muzzle-loaders) with a 40 caliber bullet in the 450B. I recovered some of the sabots and they had a nice 1/2 round divot in the skirt --- the same diameter of the gas hole. (that didn't work)