A QUICK "PRIMER" ON 556 AMMO
The 5.56x45mm NATO cartridge has a storied history, developed in the 1960s to meet the evolving needs of NATO forces for a lightweight, high-velocity round suitable for modern combat rifles like the M16 and AR-15 platforms. This cartridge is known for its speed, accuracy, and relatively low recoil, making it a versatile choice for a range of shooting activities. Standard 5.56 NATO rounds typically use a 55-grain or 62-grain bullet, but you'll find options ranging from lighter 45-grain loads up to heavier 77-grain loads, each catering to different shooting preferences and applications
One common point of confusion among shooters is the difference between 5.56x45mm NATO and .223 Remington ammunition. While they appear nearly identical, there are important distinctions. The 5.56 NATO is loaded to higher pressures and has a slightly longer throat in the chamber, allowing it to handle this increased pressure. It's generally safe to shoot .223 Remington ammo in a 5.56 NATO chamber, but firing 5.56 ammo in a .223 Remington chamber can lead to increased chamber pressure, which isn't ideal for the firearm's design and could pose safety risks. Note: Using 556 ammo in a 223 Wylde barrel is OKAY (rated for higher pressures). It's crucial to know your rifle's chambering and stick to the appropriate ammunition.
In terms of options, Federal's XM193 and PMC's X-TAC are standout choices that consistently rank high with our customers. Federal XM193 is a 55-grain FMJ round built to military specifications, offering reliable performance that's perfect for training or tactical applications. PMC's X-TAC line provides both 55-grain and 62-grain options, designed for shooters who demand consistent accuracy and reliability in every round.
TOP CONSIDERATIONS WHEN BUYING 5.56 NATO AMMO
When buying 5.56 NATO ammunition—whether you need bulk 5.56 ammo or specialized self-defense loads—it's helpful to consider your intended use and understand how different load types perform.
Purpose: For range training and target practice, FMJ (Full Metal Jacket) rounds are affordable and perform well. If you're considering ammunition for hunting or self-defense, look into soft-point (SP) or hollow-point (HP) rounds, which expand upon impact, causing greater energy transfer and stopping power.
Bullet Weight: Bullet weight affects how a round behaves at different distances. Lighter bullets (like 55 grains) are fast and offer a flatter trajectory, making them ideal for short to medium distances. Heavier bullets (62 grain, 70 grain, 77 grain, or even 80 grain 5.56 ammo) maintain momentum better and are less affected by wind, offering advantages at longer ranges.
Choosing a Manufacturer: Stick to reputable brands with proven consistency. Federal's XM series is a go-to for many shooters seeking reliable, military-spec ammunition. PMC provides high-quality, affordable options suitable for various applications. Winchester and Hornady also offer specialized loads that cater to different shooting needs.
Consider Barrel Twist Rate: If you're serious about accuracy, know your barrel's twist rate. Faster twist rates (1:7) stabilize heavier bullets (62 grains and up) more effectively, while slower twist rates (1:9 or 1:12) are better suited for lighter bullets (55 grains or less). Many modern AR-15s feature a 1:8 or 1:9 twist, offering versatility across common bullet weights.