Delta Force was an early adopter of a lot of civilian competition gear into military service, and the modern AR-10 is a great example. Delta worked with Knights Armament to fine-tune the SR-25 rifle, with it first being used by Delta, then being adopted by the US Navy, and eventually by the Army as the M110 SASS. What we have here today is a further development after the adoption of the sniper pattern like the M110. Delta wanted something with sniper-level accuracy, but short enough to use in urban combat and building clearing operations. Knights obliged, and this rifle (the upper, that is) is one of a batch that were purchased in 2012 or 2013 by Delta. However, shortly after these were acquired, Knights released an improved version of the railed handguard, and Delta opted to send back their EMC (Enhanced Military Carbines) for replacement with the newer version. Knights took those returned guns, put the uppers onto new-production semiauto lowers, and sold them off on the civilian market quietly. Surplus arms from the US military in any form are pretty rare these days, and surplus equipment from Delta Force is extremely rare, making these a really cool example!
Note that when I filmed this, the suppressor had not yet transferred, so I didn’t have access to it. It has since cleared, and is included with the rifle at Morphy’s this week (Lot 3010, on Thursday, July 14th).