Winchester White Box USA 5.56x45mm NATO Ammo 55 Grain Full Metal Jacket

Winchester White Box 5.56 55 grain FMJ ammo delivers reliable M193 5.56 ball ammo for training and range days. Additionally, this bulk 5.56 range ammo keeps cost per round low for high-volume shooters. It also works well as AR-15 training ammo for new shooters learning the platform. Furthermore, this brass reloadable 5.56 ammo lets handloaders recover cases after firing.

Winchester USA 55gr FMJ 5.56 Ammo Specifications

• Caliber: 5.56x45mm NATO
• Bullet Weight: 55 Grain
• Bullet Type: Full Metal Jacket (FMJ), M193 profile
• Case: Brass, boxer-primed, reloadable
• Muzzle Velocity: Approximately 3,240 fps
• Rounds Per Box: 20
• Application: Range training, target shooting, AR-15 platforms

M193 5.56 Ball Ammo Built to Military Spec

M193 5.56 ball ammo like this Winchester load follows the original military specification for 55 grain FMJ ammunition. Because the bullet profile matches M193 dimensions, it cycles reliably through most AR-15 platforms. Also, the flat-base FMJ design feeds smoothly from standard magazines. Shooters can browse the full rifle ammo lineup for other M193-spec options, or compare against dedicated 223 Remington ammo for bolt-action rifles.

Bulk 5.56 Range Ammo for High-Volume Shooters

Bulk 5.56 range ammo like this Winchester load keeps cost per round manageable for frequent range trips. In addition, the consistent FMJ bullet weight helps shooters build muscle memory without changing point of impact. As a result, this load suits both practice sessions and casual plinking. For heavier-grain options, compare against our Winchester M855 SS109 62 Grain load.

AR-15 Training Ammo: Winchester USA 55gr FMJ 5.56 Ammo Advantage

AR-15 training ammo like this Winchester load helps new shooters learn recoil management and trigger control affordably. Also, the FMJ profile is easy to clean afterward compared to lead-tipped hunting rounds. Therefore, this load is a smart choice before stepping up to premium hunting ammo. For a lead-free hunting option instead, see our Barnes VOR-TX 70 Grain TSX load.

Brass Reloadable 5.56 Ammo for Handloaders

Brass reloadable 5.56 ammo like this Winchester load gives budget-minded shooters a path to lower long-term costs. Furthermore, boxer-primed cases accept standard reloading dies and components. Handloaders can also pair recovered brass with our 5.56x45mm NATO ammo lineup when sourcing bullets and components. In short, this Winchester load rounds out a well-stocked 5.56 ammo supply for reloaders and range shooters alike.

Winchester USA 55gr FMJ 5.56 Ammo FAQs

What twist rate works best with this ammo?

Winchester White Box 5.56 55 grain FMJ ammo performs best in barrels with a 1:9 or 1:7 twist rate. Specifically, a 1:9 twist stabilizes this lighter 55 grain bullet very well. Faster twists like 1:7 also cycle it reliably, though they are tuned for heavier bullets. Therefore, most standard AR-15 barrels handle this load without issue.

Is this ammo safe to fire in a 5.56 chambered AR-15?

Yes, Winchester White Box 5.56 55 grain FMJ ammo is loaded to 5.56x45mm NATO specifications and is safe in any properly headspaced 5.56 chamber. Additionally, it also safely cycles through .223 Wylde chambers. However, shooters should avoid firing 5.56 ammo in a rifle marked .223 Remington only, since chamber pressures differ. Always verify your barrel markings first.

Does this Winchester USA 55gr FMJ 5.56 ammo use reloadable brass?

Winchester White Box 5.56 55 grain FMJ ammo uses boxer-primed brass cases that are fully reloadable. As a result, handloaders can recover and reuse spent cases after firing. In addition, Winchester brass is known for consistent wall thickness and long case life. This makes it a solid choice for high-volume reloaders.

What velocity does this ammo produce?

Winchester White Box 5.56 55 grain FMJ ammo produces approximately 3,240 feet per second from a 20-inch test barrel. Specifically, velocity runs somewhat lower from a shorter 16-inch AR-15 barrel. Therefore, shooters should chronograph their own rifle for exact data. Always review safe handling guidance from the National Shooting Sports Foundation before heading to the range.

How should I store this Winchester USA 55gr FMJ 5.56 ammo?

Winchester White Box 5.56 55 grain FMJ ammo should be stored in a cool, dry place away from direct sunlight. In addition, keeping ammo sealed in its original box prevents moisture exposure. Therefore, a sealed container or ammo can adds extra protection long term. Proper storage preserves reliable ignition for years.