Very awesome cartridge that Rem can chalk up as their marketing fails. Along with the 6mm rem, 260 rem, 8mm rem mag, 17 firball.. All incredible rounds that Remington failed to market.
This round is probably the king of AR-15 chamberings as far as 100-300 yard energy goes (excluding the 450 bushmaster, 458 socom and 50 Beowulf). I can push a 130 TTSX almost 3000fps out of mine with a hot loading. After 300 yards the Grendel will take over due to brute B.C.
The problems with the Rem 30 AR is that its a highly propriotary round. The bolt, BCG, barrel, magazine, are all specific to this round.. So it lacks the modularity of other SAMMI spec AR cartridges. Also, Remington is the only Brass/ factory ammo maker for this round, which they have neglected horribly... The only seem to do a run of it every year or two..
Too bad, because it really is a great gun to shoot, and even better for woman or smaller stature shooters.