I can vouch for 2 3/4" Brenneke rifled slugs. Some 20 years ago I was on a month long hunting & fishing trip in the top end of Australia. At that time the National Parks & Wildlife decided to eradicate feral water buffalo from northern Australia due to concerns that a turbuculousis outbreak may spread to the cattle industry.We were mainly up there pig shooting so the biggest rifles we had were 308, but we also had a Browning A-5 semi auto shotgun with 2 3/4" Brenneke slugs. We were invited to several water buffalo culls & the slugs dropped buffalo in their tracks when shooting at 50 yards. I personally accounted for 4 water buffalo with 5 shots fired within 10 seconds with rifled slugs from the Browning.I now reflect on those days when I see water buffalo guided hunts with a $3000 trophy fee per buffalo.Although we didn't have 3" slugs to compare(probably would have used them if we had them), I can't fault the 2 3/4" rifled slugs on water buffalo at up to 50 yards.