I see a lot on the internet that says that .223 in 1:9 twist can stabilize up to a 75 or so grain bullet. I've also seen mentioned a time or two that at higher elevation that you can stretch that limitation up to 77 or maybe even 80. Has anyone had any experience with a 77 grain or larger bullet in 1:9 twist here at altitude? Gun is a Savage 24" bull barrel bolt gun.