Allen: VG may have different recommendations but I currently shoot five .204's using just two loads. For coyotes it's the 35 grain Berger in front of 26.0 gr Benchmark. For varmints, I shoot 39 grain BK's over 25.0 gr Benchmark. There are other loads that work well--some maybe even slightly better but these two loads shoot very well in ALL my rifles. (Sixes or less for five shots at 100 yards.) Niether load is maximum but it sure simplifies my loading. I would not be afraid to stay with the Bergers for ground squirrels since you (I anyway) generally run out of ground squirrel before I run out of trajectory and wind drift. But, as Jim stated, the BC is much better on the BK's for colony varmints.
To the OP: I did have the 39 BK's start key-holing in my 12-twist DPMS upper and thought I was done with that bullet as well. Outside of maybe a more thorough cleaning, I'm not sure why they quit key-holing but they are shooting great in it again.
I use Butch's then leave WipeOut in my barrels overnight (sometimes more than one time) until my patches are almost void of blue. Good luck.
