Depends on what you are shooting but 39 and 40 grain bullets worked well for me on Coyote and squirrel. I am shooting 26 grain Varmint Grenades now with AA2230 and it works fine.
I have two 204's. The Ruger Ultralite really likes 32 grain Vmax and Benchmark (around .5" consistently). It won 't shoot 40 grain Vmax at all. I am now shooting 35 grain Vmax and Varget with around .75" groups. My WOA AR shoots the 35 grain Bergers with Benchmark into 3/8" groups consistently and I quit trying other loads when I tried that one when I first started working up a load. I don't think I am capable of shooting any better than that. My experience with other people's 204's is that they seem to prefer specific bullets and not like others. I have a friend who has two identical rifles and one shoots 32 grain Vmax very well and won't group 40 grain Vmax at all. The other rifle is just the opposite. It doesn't make sense but that is what makes working up a load interesting.
Originally Posted By: Varmint Master35 GRN Bergers and H4895
What he said. I might add, if you are looking for a BT bullet,
the Sierra 39 gr. Blitzkings were the most accurate next to
the 35 gr. Berger, in my Savage 16. Same powder.