Sellier and Bellot 223 caliber (556 NATO M193) Imported from the Czech Republic, this ammo is current production and made to military specs Inexpensive and very accurate because of the Full Metal Jacket bullet Non-corrosive, Boxer-primed brass case, reloadable 3,301 fps, 1,352 foot-pounds Simply put, this is some of the best and most accurate ammo on the market today at a great price