Originally Posted by MudRunner2005
If I'm not mistaken they're still using some of them in AR platform DMR's for special purpose uses. 6.5 Grendel is a cool little caliber. Alot of people overlook it for the 6.5 Creed and .260 Rem. The 6.5 Grendel will stay supersonic a long ways after the .308 Win goes subsonic.
I've thought about building a bolt 6.5 Grendel, but the only drawback is that it has such an unusual bolt face (same as 7.62x39 and 6.8 SPC), which is not commonly found in bolt guns.
Not an issue with battle rifles where 400yds is generally max range and most fights are occurring at sub 100yds.
The Grendyl had lots of problems with feeding and overheating barrels.
The 6.8SPC is a much better short range caliber.
The cost of changing over to a new caliber in service rifles is just too much in a time of drawdown so you won't see any changes other than for SOCOM where special needs take precedence.
One consideration will always be resupply on the battlefield especially on long ops where supply drops are difficult or impossible. No matter where you go in the world you can find 7.62x39, 7.62x51, or 5.56 so that's probably where we'll stay for at least the next 20-30 years.