Can't hardly find these shells anywhere around here. Finally located a box and gave them a try yesterday afternoon. Gained about 20 pellets from the 2oz loads
Long Beard Magnum 3.5" 2-1/8oz #5's 40 yards lasered
Rem 870 SM 28" with Hevi-shot .662 Choke
Forcing Cones Cut and polished
Wish I could find a box of 3" 1 7/8 oz. around here to compare to the lighter load. Wonder if it is the reduced speed, more shot or a combination of both that increased your pattern that much? You gained just about every pellet the extra 1/8 oz. gave you.
Were the temperatures and conditions near the same as your first testing with the lighter load?
Pretty close I'd guess. I don't really pay that much attention to those things because of timing.