On the winter coyote here, by far the best(consistent) terminal performance I have seen is with the BIB 40 gr hp. Extremely accurate bullet also. The slightly lower velocity from a 20p vs the 204R does help performance on some of the tipped varmint bullets. Running hot loads in my 10 twist 204R, the 32 and 40 vmax or 39 BK just don't penetrate well at closer ranges or on frontal angle shots(often called coyote). The 39 gr TNT seems interesting, but I just haven't tried them since I have plenty of BIB 40 and 40 NBT. I'll probably try the TNT in the 20p first, I should be able to run them above 3500 fps.