Dave I have shot a lot of 490-500 grain pp bullets in a 45 2 1/10 and 45 2 4/10th, in fact I killed a 5x5 whitetail buck, 2 antelope bucks and a couple of antelope does with both guns and that range of bullet. It worked very well. All shots were from 134-200 yards. None of the animals made it 40 yards. I like a .441 bullet patched with 9 lbs onion skin paper. It leaves a .001 a side for shooting dirty. I have also used a .440 bullet patched with the same paper with good results. I am not sure how a 450 would fly. Let me know
85 grains of Fg express in the 2 4/10th
70 grains of Fg express in the 2 1/10th
Both bullets had straight sides.
Stephen