SOCOM Looking at .260 Rem and 6.5 Creedmoor Sniper Systems

[stanc]

Interesting. I've only ever used a 260 Rem in the AR10 platform.. I remember when Hornady first advertised the 6.5 Creedmoor, one of the big pushes were it's disign was with semi-autos in mind.. I understand the shorter case would make performance tuning a little easier, but wouldn't the longer, less steep shoulder on the 260 Rem make it a more reliable feeding cartridge?

Perhaps. 7.62 NATO development initially used a 30-degree shoulder (3-7 below), but it was later changed to 20 degrees (8-13) due to concerns about feeding and chambering.