This Frontier load is 5.56 NATO ball ammo cut to the familiar M193 pattern: a 55 grain FMJ at 3,240 fps. It is loaded to NATO pressure, so run it in 5.56 or 223 Wylde chambers rather than tight 223 match throats, and it will feed through any AR-15 pattern rifle without complaint.Like the rest of the line, it comes 250rds loose in a latching ammo can that earns a second life as range storage. Current runs are the anniversary combo with a Hornady hat and sticker packed inside. For AR shooters who buy ammo by the case, the format is hard to argue with.