Not in favor of this. 308 cal semi auto rifles are quite heavy and so is the ammo. 5.56 actually performs very well at the ranges it’s normally used at, often it outperforms 308 in terminal ballistics on unarmored targets. The only place it struggles is defeating certain intermediate barriers.
If barrier penetration is an issue, the solution is 6.8 or 6.5. The conversion can be made by swapping uppers and mags. The cost can be defrayed by surplusing the 5.56 uppers, mags, and ammo. Since the uppers are not serialized parts, they can be surplused without running afoul of NFA / Hughes Amendment restrictions.
Ditto. I would go with 6.5 Creedmore over 7.62x51 at this point. By a mile. There is nothing the 7.62 can accomplish that the 6.5 Creedmore could not accomplish. Let the 6.5 and 6.8 duke it out the the .30 Cal and may the best round win.