I don't think it will be any flatter than 450 and pretty sure not a 458, but it sure has a lot less recoil if the advertising chart is for real.
Does about 2,100fps from a 16" barrel with a 180.
Tex, great minds think a like, I just didn't realize there were so many great minds!
I got as far as seating bullets in an expanded 223, but didn't want to screw with trying to get it to feed in an AR.
I understand it works best with the new 300 BLK magazines - mags with the front vertical rib removed.
