I have a copy of the program Shotshell Ballistics for Windows by Ed Lowry. Haven't used it in a long time. But this topic got me to open it up and run some numbers. It has a module called Pellet Penetration. It does not have #10 shot as an option, so I used #9 instead. I choose the slowest 3-ft velocity, 1040 ft/sec. Skeet choke with a 12ga 2 3/4" shell. (Hey it was never designed for a muzzle loader!) At 20 yards, the average pellet velocity is 699 ft/sec, 0.82 ft/lb with a penetration of 0.99 inches. If we increase the 3-ft velocity to 1250 ft/sec, the penetration is 1.18".
So at the author's 15yd to 25yd stated range with the pattern density of this load, we can expect at least 10 - 15 hits on target.
Pete
