How is it that you pre-determined the powder charge? Most folks try different charge levels and see which ones group the best. I would suspect that 125 grains would be a little on the hot side for 3F Triple 7. Might start working up at 5 grain increments from about the 90 grain level and see what happens.

If you want to use a Nosler Partition in that weight range, I would recommend a 260 grain .451 bullet with a 50/45 Harvester sabot; or just get the pre packaged Jim Shockey loads. They have a pretty well established track record on big game.