Winchester USA White Box M193, 5.56x45mm NATO, 55 gr FMJ, Rifle Ammunition, 600 Rd Case Winchester USA White Box is one of the most trusted names in range ammunition, and this M193 load is the standard 5.56x45mm NATO training round. Each cartridge pairs a 55 grain full metal jacket bullet with a brass case at a muzzle velocity of about 3,240 feet per second. This listing is a 600-round case: four 150-round boxes. The 150-round box is a big step up from 20-round packs. It means less time opening boxes and loading from loose rounds, and it is easy to stack and store. Winchester heat treats and anneals the brass for better ductility, so cases cycle reliably and are good candidates for reloading. Shop the Winchester USA White Box M193 5.56 600 Rd Case at BattleHawk Armory. A Range Staple for the AR-15 M193 is the 55 grain ball load that the 5.56 NATO cartridge was built around. It runs well in AR-15 rifles and carbines with 1:7, 1:8, or 1:9 twist barrels and in other rifles chambered for 5.56x45mm. The full metal jacket bullet feeds smoothly and holds up well for drills, zeroing, plinking, and high-volume training classes. Buying a full case keeps enough on the shelf for several range trips or a full training course. Because Winchester loads this ammunition to consistent standards, point of impact stays steady from box to box. That makes it a dependable choice for practice that matches what you shoot with other 55 grain loads. Need a smaller amount? Get the Winchester USA M193 5.56x45mm 55 gr FMJ 20 Rd Box. For even more volume, see the Winchester USA M193 5.56 1000 Rd Case. Product Specifications Manufacturer: Winchester Product Line: USA White Box (Target & Practice) Caliber: 5.56x45mm NATO Load: M193 Bullet Weight: 55 gr Bullet Type: Full Metal Jacket (FMJ) Case Material: Brass Primer: Boxer Reloadable: Yes Muzzle Velocity: 3,240 fps Muzzle Energy: 1,282 ft-lbs Rounds Per Box: 150 Boxes Per Case: 4 Rounds Per Case: 600 Application: Target and range shooting, training Made In: USA Manufacturer Part Number: WM193150 UPC: 020892225015 Frequently Asked Questions How many rounds do I get? 600 rounds: four boxes of 150. What bullet does this load use? A 55 grain full metal jacket bullet, the standard M193 ball load. How fast is it? About 3,240 fps at the muzzle with about 1,282 ft-lbs of energy. Will it run in my AR-15? Yes. It is loaded for rifles chambered in 5.56x45mm NATO, including AR-15 rifles and carbines. Is the brass reloadable? Yes. It uses boxer-primed brass cases that can be reloaded. Order Winchester USA White Box M193 5.56x45mm 55 gr FMJ by the case at BattleHawk Armory.