Hornady 150gr FMJBT works very well. Load it to 2.850" OAL
I have 2 K31's.. A 6X leupold rifleman sits on one and a Swiss diopter on the other. The price of the latter was tough to swallow at first but I haven't regretted it. Both rifles are good shooters. Since the range I go to no longer allows FMJ rifle ammo, I rely on my handloads.
How about 168gr Sierra Match Kings? I have a bunch of those and 7.5x55 dies, and some boxer brass, just haven't tried making any yet. Any powder suggestions?
Regarding GP-11 the first time I fired in on my 600 yd. target, which is made of 5/16" diamond plate steel, I was stunned to see that some of the bullets completely penetrated the target!
35W