I loaded them this year for my 264 win mag with IMR 7828. It was shooting about 3200 fps with 140 gr Gamekings and 0.6" groups @ 100yds. My dad used that gun this year and shot a nice 5x5 whitetail and a 2 1/2 yr old bull moose. Didn't find the bullet from the whitetail but the one from the moose came out looking great, also about 90%, haven't weighed it yet.
Another great bullet is the Nosler Accubond. Super accurate and talk about picture perfect petals after impact. I shot 2 moose and 2 deer with them out of my 300 WBY and had great success. But the Noslers are also twice the price.
Both are great bulllets, which one is better ? The GameKing is a great bullet, proven killing track record, flies great and the price all make a combination that is virtually impossible to beat. Yeah, you can spend more but why ?