Now you are talking. That's my favorite gun. I have 4 lymans. The GPR is actually a 1:60 twist. You have the GPH which is 1:32 twist. I took 3 deer this year with mine. I get less than 2" groups at 100 yards using 100 gr Triple 7 and a 425 gr Hornady great plains conical. Mine will shoot maxi balls , maxi hunters and modern sabots but shoots the Honady the best. I took a deer at 118 yards this year and it didn't go 15 yards when that conical slammed into her. You will love the gun. Have fun experimenting