I had the same problem with inconsistent numbers and inconsistent poi with the fed hwt 7s. Would shoot 170s and then next shot 80s and 90s. Trulock choke would get the highest numbers but everything I tried had inconsistent results. I sold all of my heavyweight because I was so frustrated with them and I went back to shooting hevi 13. My 870 loved hevi 13 7s but the 6s were what I hunted with. It shot very even patterns with the sixes and was consistently in mid to high 120s. Ended up selling it to a friend of mine but I have another one to get ready. I have two single ahot 20s that had the same problem with the heavyweight 7s.