Thinking about building a 450 Bushmaster 16" rifle, anyone have some experience with this caliber. Type of dependable mags and or replacement and brand followers, I have pmag, hex mags, and lancer mags . Want to use 165-230 grain 45 acp bullets for reloading since I have a great supply of . Any feed issues with certain bullet profiles ? Powders ? ect. Any helpful advice would be appreciated.