I always used 300 grain bullets in mine, for everything that I've pointed it at. I like the way 300 grain Nosler Partitions that fly from my rifles and especially from the .375 H&H.
Never really had a complaint, although I had one that didn't quite penetrate deeply enough on an Alaska/Yukon bull moose at 700+ yards that a client had wounded and which I was trying to prevent from escaping. But, I hit a shoulder blade. Even still, it got into the chest cavity.
And I once had another client-wounded bull moose which was directly below - virtually straight below - at about 20 feet and the bullet ricocheted off the left shoulder, without penetrating the skin (even).
However, in terms of deer-size game, I've always had plenty of penetration with 300 grain Partitions. I once whacked a Sitka blacktail buck on Kodiak Island, that was somewhere over 400 yards, and the 300 grain Partition bullet went clean through to the hide on the off-side.
