Exactly, however if you are shooting beyond 300-400 yards you aren't too concerned with MPBR. You are either dialing or holding over. The OPs original question was flattest shooting cartridge with the furthest MPBR on a 4" target. To accomplish that feat the projectile needs to be moving in...
I originally put it together for my sons and daughter to hunt with but they all prefer the 308. My oldest still hunts with a 7-08 but a different rifle. This is a really good shooter but is just not being used. Scope is only about a year old or less. Great rifle! I have some ammo I would include...
22-250 AI/FT is the flattest shooting cartridge I own to 500 yards. It will stay in a 4" circle to 308 yards, according to my ballistics calculator, with a 50 gr BTV with a BC of. .267. It will launch them at 4000fps from a 27in barrel. Mine has a 27" Krieger with a 1/8 twist. Carries just over...