You need to keep in mind the possibility of feeding issues with standard magazines if you to to odd ball.
TAB's typing skills must be contagious Tom...
Good luck with the odd ball TAB,...mags, and bolts maybe a pricey addition, but if it's where you want to go,....may I humbly consider .50 Beowulf, or .458 SOCOM? Ammo prices are bad enough...
or just get the 9mm conversion for cost.....which also NOW sucks.