5.56x45mm – 62 Grain M855 FMJ – Winchester (WM855K) – 1000 Rounds

M855 green tip is the 62 grain 5.56 round that many AR owners train with and keep on the shelf. This listing is Winchester USA M855 5.56x45mm NATO 62 grain green tip full metal jacket ammo, MPN WM855K, sold as a 1,000 round case packed in 20 round boxes. It suits carbine training, steel matches, and long-term storage. Shooters who use it for long-term storage appreciate that the boxes stack neatly in standard ammo cans.

Winchester rates WM855K at 3,060 fps with 1,289 ft-lbs of muzzle energy. The 62 grain M855 style bullet is longer than 55 grain ball and stabilizes best in faster twist barrels. It is loaded to 5.56 NATO pressure. M855 type bullets include a steel insert, and many ranges ban them because they can damage steel targets and backstops. A full metal jacket bullet does not expand, so this is training ammunition, not a hunting or defensive load.

It fits rifles chambered in 5.56x45mm NATO with a 1 in 7, 1 in 8, or 1 in 9 twist, which includes most AR-15s from Colt, Daniel Defense, BCM, Aero Precision, and Ruger, plus the FN SCAR 16 and IWI Tavor. A common question is whether green tip is allowed at my range. Many indoor ranges and some outdoor steel ranges prohibit it, so check before you go. Another common question is whether a 1 in 12 twist barrel stabilizes 62 grain M855. Often not, and you may see keyholing, so faster twist rates are recommended.

Winchester WM855K is new production ammunition, not reloads, made in the USA. Cases are reloadable brass with boxer primers, and the load is non-corrosive. This listing ships as 50 boxes of 20 rounds, 1,000 total, all from one lot. Twenty round boxes store well and let you load exactly one standard magazine at a time. Keep the case dry and away from heat and it will stay reliable for many years.