IMO the 243 has an advantage as a varmint cartridge if you take advantage of the ability to shoot the 90 and 100 grain bullet. The 243 shines with a 100 grain pill at or over 3,000 fps.

When you drop down to the 75 grain pill and lower you loose your advantage. The 22 caliber 75 grain bullet has a better BC than the 75 grain 243 pill, with approximately the same velocity.

Try the 100 grain Nosler Ballistic tip. You should get great long range capability out of that bullet. Tom.