Following: I was about to post the same question. Buddy has a Winchester 20ga and is diving into the TSS waters. He has Apex Ninja 8.5s and Federal #9s. He is trying to decide between Trulock .565, Sumtoy .562, Sumtoy .570, LongBeard .568 or Carlsons .575. Other suggestions welcome. I am not familiar at all with the Winchester. Thought I read somewhere that even the 20 gauge winchesters have backbored barrels.