Perfect Varmint Caliber???

[Cossack]

I shoot the following that fall into the category:17 Rem, 17 HMR, 22LR, 22 WMR, 22 Hornet, 223, 22-250 and 6-284.
If you load, 22-250, or perhaps 204, depending on what you're using it for.
If not, 223 with Black Hills ammo, Red box or Black in a load that matches your barrel's twist rate best.