I've only shot one 444, a couple times, using my 280 gr WFN, pb, zipping along at 2450 fps, and it would print into an inch fairly consistent. The neighbor who brought it over to have me try it did lap the dickens out of the barrel till it was super smooth and straight, and that was here in cool Northern Idaho.
If the bore is lapped well one should be able to get very good accuracy with PB at speeds to 1500 - 1600 fps even down in the hot country. Up in your bear country the 1600 fps top end which I recommended should be a cakewalk.