They should work real good in your rifle. Just make sure you do not put a lot of powder behind them. I shoot the 460 grain out of my .50 caliber with 80 grains of Goex FFFg or Pyrodex P and get fantastic groups. The next time I want to try putting a wonder wad under them. I heard it made better groups but actually I shot six 460 grain No Excuse conicals into a one in square box (would have covered the group) at 35 yards. At 50 yards that opened to an inch and a quarter. I have not had a chance to get back to 100 yards but I do expect around a two inch group....

I was shooting a T/C Black Diamond XR with a 4.5 power scope setting. I would suggest starting your load out at 70 grains of FFg and work up from there. I almost always shoot FFFg in everything .50 caliber and smaller and FFg in the .54's, .58's & .62 caliber rifles I have.