My dad had one in a .338 WM and shot the Federal 210g Partitions. It grouped 3/4" at 100 yards. He took a couple spike elk with it, and one was 500+. The recoil is not that bad. Its a semi auto, it soaks up quite a bit. I dont think you'll need a BOSS, but obviously you said you want one. My dads did not have the BOSS and we had no problems getting 3/4" off the bench. Another note, one of my elk hunting buddies has shot a 300 WM in a BAR for 20+ years. He has shot a bull every year with it. It is also very accurate and has taken elk out to 600 yards. Browning BAR's are very nice rifles. You wont go wrong with either.