1000 Rounds Winchester Lake City 5.56 NATO 62 Gr. Green Tipped FMJ M855 packaged in 20 round boxes - WM855K - Q3269 - Same as XM855

Winchester USA White Box 5.56mm NATO M855 62-grain "Green Tip" Penetrator Full Metal Jacket (Product Code: WM855K).

If there is a single rifle round that represents the backbone of civilian tactical training and bulk ammunition stockpiling, this is it. Synonymous with the "Green Tip" moniker, the WM855K SKU is Winchester's mass-commercial 1,000-round bulk packaging configuration. It takes military-grade components directly off the production lines and packages them for high-volume civilian shooters.

Overview & The Lake City Heritage

Like its sibling SKUs, the magic of the WM855K is its manufacturing pedigree. It is produced at the massive Lake City Army Ammunition Plant in Independence, Missouri—the exact same facility that supplies the United States Armed Forces.

You may frequently see this exact same ammunition listed under two different Winchester item numbers: WM855K and Q3269.

• WM855K is Winchester's standard commercial retail designation (often sold in "USA White Box" lines).

• Q3269 is Winchester’s internal military/government contract coding.

Functionally, they are identical. Both roll off the exact same Lake City production lines, utilize the exact same 62-grain steel penetrator bullet, and are packed into 20-round boxes. At Eagle Eye Guns, we supply whichever SKU gives you the absolute best bulk pricing at the moment.

• Caliber: 5.56x45mm NATO (High pressure; never fire in standard .223 Rem chambers)

• Bullet Weight: 62 grain

• Bullet Type: M855 Full Metal Jacket Boat Tail (FMJBT) with a steel penetrator core

• Casing: Lake City brass, factory annealed (heat-treated for durability)

• Muzzle Velocity: ~3,060 ft/s

• Muzzle Energy: ~1,289 ft-lbs

• Packaging: 1,000-round master case (split into fifty individual 20-round white boxes)

Performance and Ballistics

1. The Steel Penetrator Core

The defining visual trait of the WM855K is its hand-painted green tip. Beneath the copper jacket sits a two-part core: a standard lead base capped by a 7-grain, hardened steel cone (the SS109 penetrator). This configuration was originally engineered by FN Herstal to give infantry rifles better barrier penetration out past 300 yards. Against hard intermediate targets like heavy sheet metal, car doors, or thick wood, it performs exceptionally well, punching clean holes where standard 55-grain lead bullets might smash apart.

2. Full-Throttle NATO Velocities

Winchester doesn’t down-charge its commercial white-box line. The WM855K is loaded to maximum SAAMI/NATO pressures, screaming out of a 20-inch barrel at over 3,060 ft/s (and maintaining roughly 2,900+ ft/s out of standard 16-inch carbines). This provides crisp, positive, and aggressive cycling in gas-operated firearms, easily blowing past stubborn carbon build-up in a dirty gun.

3. Extended Range Stability

Because the 62-grain projectile is slightly longer and heavier than traditional 55-grain M193 ball ammo, it boasts a superior ballistic coefficient. Once you push your targets out past 200 yards, the M855 profile holds its velocity better, resists crosswinds more effectively, and drops less vertically, making it a highly predictable range round for medium-distance outdoor steel training.

Pros & Cons

Pros

• Premium Lake City Brass: The casings feature visible neck-annealing (dark coloration from the factory heat-treatment), making them incredibly strong, highly elastic, and a premium choice for reloading.

• Perfect Stockpile Ammunition: Between the sealed primers, robust boxer priming, and thick mil-spec brass, this ammo is structurally built to sit in long-term storage or sealed ammo cans for decades without degrading.

• Extreme Feed Reliability: Features a smooth, uniform boat-tail profile that feeds flawlessly up aggressive M4 feed ramps without scarring or jamming.

Cons

• The Indoor Range Ban: Because the steel tip will easily dimple, crater, and destroy steel target plates—and poses a distinct spark/fire hazard on indoor backdrops—virtually all indoor commercial shooting ranges strictly ban this ammunition. (Always check with a magnet before bringing it to a range).

• Tissue Performance Limitations: In close-quarters defensive scenarios against soft tissue, the M855 core is notorious for ice-picking straight through a target without expanding or yawing until it hits a depth of 7 to 8 inches. It is built to defeat light armor and barriers, not to expand like a dedicated home-defense jacketed hollow point.

• Twist Rate Dependent: To get the best accuracy out of this heavier 62-grain projectile, your rifle requires a fast 1:7", 1:8", or 1:9" barrel twist rate. Standard, slow-twist vintage barrels (like older 1:12" civilian rifles) cannot stabilize the longer bullet, causing it to "keyhole" through the air.

The Verdict

The Winchester USA WM855K 1,000-Round Bulk Case is an absolute gold standard for high-volume shooters looking to feed a hard-use AR-15 platform. While its steel core means it belongs strictly at outdoor ranges or open land training fields, its flawless Lake City cycling and robust ballistic pedigree make it one of the single most reliable "do-it-all" bulk 5.56 packages on the market.

• The Takeaway: AI can sometimes make mistakes, but it's never a mistake to secure your bulk cases from Eagle Eye Guns.