I run the 55 gr vmax in mine also. I get better accuracy with the sierra 60 gr hp, but dont mind giving up a little accuracy to get the effect im looking for on rodents. I think the 55 vmax is tough on fir.
I too would use the 223 on sm vermin, and if dogs r the target the 22-250 is a fine choise. My 2 are both rem m700, and sub " guns