Mike, sorry about the terrible spelling in my last post to you. Up all night in shop working on molds. GRRRRR!!Mike
I’ve noticed the same thing out of my rainstorm 30. The 50 grain jsb have a slightly higher bc and I like them for close range work but can’t touch the 50,55 grain Nielsen slugs for longer ranges. The 50 jsb vary in weight more so than the 44.75’s also. And the Nielsen are really consistent and accurate. I believe the barrel is also 1-26. The bbt hp 66 grain I shoot are stellar at holding energy out to 100 yards and have an even better bc. They push faster than the heavier Nielsen because of less bearing surface, but I have to weigh and sort them. Hard to beat the consistency of swagged slugs. I may have missed it.. what is your port on the cobra valve??