09-15-2014, 12:56 AM
rwh Wrote:I was confused by the way this thread started out as a comparison of grendel in AR15 vs 308 in an AR10 followed by a comparison of a 308 bolt gun shooting hand loads to a grendel shooting factory ammunition. I was also thrown by the big difference between the trajectory I got from Sierra Infinity Suite compared to what bigbear_98 was getting from the JBM ballistics engine. I think it is time to retire Sierra Infinity as JBM confirms what I've suspected all along, which is that getting a grendel to shoot to 1000 yards, while possible, is roughly equivalent to trying to get an M1A to shoot out to 1000 yards. Both can do it, but neither is ideal.
I've been playing with the idea of an AR10 build, but I would probably not go with a 308 in an AR10 either. I was thinking 260 remington or 6.5x47 lapua. I would be interested if anyone has any data on how an AR10 does with hot loads. What parts on the AR10 are going to start breaking as I begin pushing loads up close to max for the cartridge. Is the AR10 really able to push the same kinds of loads one would use in a bolt gun?
Very nice shooting.
I run my AR-10s in 6.5 x 47 Lapua at 2850 ft/sec using the 123 scenar for thousands of rounds with no issues. I have pushed it to 2950, but it is not a great load in typical 22" barrels.
Makes the .308 guys scratch their heads!