I have a Remington 870 21" barrel. I shot the old federal heavyweight 3" 7s out of the carlsons tss .640 tube. It's throwing 160-180 in a 10" circle at just over 40(42) yards. I shot one of the Federal 3" TSS 9s out of it and got 321 hits. My Trulock Federal 7 .650 choke just come today. I plan on shooting the same shells through it this weekend, weather permitting and I'll post the results. It was near 70 the day I shot the Carlson, and it'll probably only be mid 50s when I shoot the Trulock. So not a 100% fair comparison, but the best I can do.