Optimum 6.5 Grendel bullet weights

[stanc]

TSX

Any weight of 100 gr or better will better the SD of the 70 gr .24" bullet. The 120 gr TSX would do just fine in this role - provided JAG allowable.

Since the 5.56mm 70gr TSX is JAG-approved, I'm sure there'd be no problem in that regard with 6.5mm TSX loads.

But, I'm not so sure the AA 120gr factory load is a good choice. From a 10.5" barrel, MV would likely be no more than ~2175 fps. Minimum expansion velocity of the 120gr TSX is 1800 fps.

For use in the Mk18, it looks to me like a much lighter TSX -- say, 85-100gr -- would be optimal, in that MV would be high enough to ensure maximum expansion in soft tissue.