I've had great success in ALL my K31s shooting 'lighter' loads, and GP11 of course. One of my favorite range loads uses some of the components you mentioned above. Hornady 150gr FMJ BT, and H4895 powder. I was using PRVI brass and Win LR primers but for the last few months I've been reloading GP11 brass with Tula LR berdan primers. 36.5 gr of H4895, 150gr Hornady FMJBT, GP11 brass FL sized and trimmed to 2.179, Tula primer, COL 2.850", this is a nice light/accurate load that is easy on the shoulder. I am able to consistently have all shots touching within an inch when shooting 3 or 4 shot groups, but Im still working on making 5 shots touching under an inch (but I believe this is more shooter related than rifle/load). Im using a clamp on scope mount with a K4 weaver mounted to accomplish this.
I'll see if I can post some pics of some target sheets, I even have a video shooting this load with great success.
Goodluck and have fun,
DeltaOps
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