User blog comment:Dolten/Favorite gun loadout/@comment-1079585-20100427215447

The REC7, previously known as the M468, is a fully automatic assault rifle manufactured by Barrett. It is extremely similar to the M4 in appearance and has commonality with some of its parts, but it fires the 6.8mm SPC cartridge, which is in between the 5.56x45 NATO and 7.62x51 NATO cartridges. Also, the 6.8mm cartridge has better ballistics than the 5.56 NATO or the 7.62x39 cartridges. The REC7 also uses a short stroke piston mechanism, unlike the M16 or M4 which use direct impingement. This makes it much more reliable. The REC7 PDW variant is just a much smaller version of the REC7.