Remington 870 Sm 26" barrel.
Carlsons .640 @ 40 lazered
Just polished barrel. 78 degrees 70 percent humidity.
Federal HW 7's 3" 1 5/8 oz. 144 in 10" +136 in the 20"
Federal HW 7's 2 3/4" 1 1/4 oz. 105 in 10"
WIN XR 6's 2 3/4" 1 1/2 oz. 84 in 10" +116 in the 20"
REMINGTON 2 3/4" 6's 1 1/2 oz. 67 in 10"
KENT diamond 2 3/4" 6's 1 5/8 oz. 73 in the 10"
Well it was a long-shot with a very tight tube.
Those 3" federal 7's are killers. I used to turn 200 with that load out of a Hastings non ported .665. Had 4 boxes of 10 of those shells and when I ran out..I started shooting the Hevi 7's for the extra shot..went from 200 to 280's with a 3" shell. Gave up some pellet weight for the extra shot. Those fed 7's are definitely a death punch.