My daughters palma rifle needs the 30 inches of barrel to make that 155 go 2980-3020, and also for iron sights. If you let her choose she will always pick her 20 inch barreled 7mm saum shooting 168 vld(2920ish) for 1000 yds. She also wants a 284win barrel for her palma rifle for matches that don't make her shoot 308.