Thread: P O Ackley

That correct Sidney, Remington chambered it in there lever and semi autos trying to find something to compete with the 270 winchester.Pressures where lowish. They try ed renaming it in the late 70s "7mm express" and quoted higher velocities but it didn't take off and created a bit of confusion so they went back to calling it .280 rem. As to the gains with the ackley improved unless your properly set up with pressure testing gear and worked up in 280 then re chambered to AI in the same barrel its just guess work but the gains are there along with a few other benefits.

As mentioned above in regard to the 280 gain, look at the gain or lack of it in the 270 ???

Originally Posted by Kiwi Greg

As mentioned above in regard to the 280 gain, look at the gain or lack of it in the 270 ???

Yeah.. getting 250fps on a 280 rem and nothing on a 270 sorta tells something about the factory loads of the 280...

You do get a wee bit extra usually on the same case with a bigger bore but 0-250fps from .277 to .284??

Heck my 6.5x55Ackley from factory loads 140s in the standard 6.5x55SE at around 2400-2500 to over 3000 is even better...