Did you ever shoot your rifle with 80 or 81gr of IMR 4831 or RL 15?

Also my 400 shoots great with Hawk 300gr .025jkt bullets and 81 gr of IMR 4831.
Velocity is @2330fps. Works great on deer and wild pigs, with less recoil than the 400gr bullets.

My double uses .408 bullets, you could probably use Hornady 300gr .411 bullets made for the 405 Winchester.