Winchester USA Ammunition 5.56x45mm NATO 62 Grain M855 SS109 Penetrator Full Metal Jacket (FMJ)

Product Overview

Winchester USA 5.56x45mm NATO 62 Grain M855 SS109 Penetrator Full Metal Jacket ammunition is a military-style green tip load engineered for reliable performance in AR-15 rifles and other 5.56 NATO platforms. Built to M855/SS109 specifications, this 62 grain FMJ penetrator round delivers dependable accuracy, consistent velocity, and smooth cycling for training, tactical drills, and high-volume range use.

About the M855 / SS109 Design

The M855, also known as SS109, features a 62 grain full metal jacket projectile with a steel penetrator core in the nose. The green-painted tip identifies it as a penetrator round designed for improved barrier performance compared to standard 55 grain M193 ammunition.

Loaded to true 5.56x45mm NATO pressures, this ammunition is suitable for:

• AR-15 rifles chambered in 5.56 NATO

• .223 Wylde chambers

• Modern sporting rifles rated for 5.56 NATO

It should only be used in firearms rated for 5.56 NATO, as these cartridges operate at higher pressure than standard .223 Remington loads.

Key Features

• 5.56x45mm NATO

• 62 Grain M855 / SS109 projectile

• Steel penetrator “green tip” design

• Full Metal Jacket (FMJ)

• Brass-cased, boxer-primed

• Non-corrosive primers

• Reliable semi-auto cycling

• Manufactured by Winchester USA

Shooters searching for Winchester M855, Winchester SS109, Winchester green tip 5.56, or Winchester USA 62 grain 5.56 will find this load a dependable option for range and training applications.

Performance & Ballistics

The 62 grain M855 SS109 bullet offers:

• Improved penetration versus 55gr M193

• Stable flight in 1:7 and 1:8 twist barrels

• Effective mid-range performance

• Consistent function in AR-platform rifles

While it can function in 1:9 twist barrels, optimal stabilization typically occurs in 1:7 twist barrels, which were originally designed for this projectile weight.

Ideal Applications

• Target shooting

• Tactical training

• Defensive practice

• AR-15 range sessions

• Bulk training use

This round is commonly used by shooters who want military-style 5.56 NATO performance in a reliable, cost-effective training load.

Winchester USA Quality

Winchester USA ammunition is known for:

• Strict quality control

• Reliable ignition

• Clean-burning propellants

• Durable brass suitable for reloading

Whether you’re stocking up for the range or purchasing bulk 5.56 NATO 62 grain M855, Winchester USA remains a trusted name in ammunition manufacturing.

Frequently Asked Questions

What is the difference between M855 and SS109?

They are essentially the same projectile type. SS109 is the NATO designation, while M855 is the U.S. military designation for the 62 grain penetrator round.

Is Winchester USA M855 good for AR-15 rifles?

Yes, provided your rifle is chambered for 5.56 NATO or .223 Wylde. It performs best in barrels with a 1:7 or 1:8 twist rate.

Can I shoot M855 in a .223 rifle?

Only if the rifle is specifically rated for 5.56 NATO. Standard .223 Remington chambers may not be rated for 5.56 pressure levels.

What does “green tip” mean?

It identifies the steel penetrator core inside the bullet, designed for improved barrier penetration.

Is this ammo reloadable?

Yes. The brass cases are boxer-primed and generally suitable for reloading.