I've shot the 160g Sierra Gamking HPBT using 77g IMR7828 and they shot well, but not great. It was a load I threw together to put my rifle on paper and also to return it to zero after I tweaked the rifle itself, this was so I had a basic load and didn't waste expensive bullets. Accuracy was around an inch at 100yds.
I haven't tried the match kings yet..... I'm sure I'll get there.. 162g Hornady A-maxes are also on the list as I have a box and a half of them sitting on the shelf. I also have a box and a half of 150g Game kings that will have a work up on them, I'll be using H1000 or IMR7828 I haven't deciede yet.
I would hunt with the 160g GK load, but I only have a handful left as they were leftovers from when I owned a 7mm Rem Mag.
I like the fact that the 7STW shoots really flat with the 140g class of bullet, but this rifle serves as a long-range rifle for both Muledeer and Elk and the STW case has the ability to launch a heavy for caliber bullet at extreme range and still have ample energy when it gets there to do the job. Running the numbers, the 175 and 180g loads still have well over 1000 Foot Pounds of energy at 1000yds and finally run out at about 1200yds. That's plenty of range for me. I'm not that good of a shooter yet.....
I just want to be sure of enough energy when the bullet gets there and have all of the ranges I shoot be covered.
Dan