XM7 vs M4: Which Rifle Reigns Supreme?

The U.S. Army is in the process of a revolutionary change in its weaponry, as the XM7 rifles replace the M4 carbines in close combat units. The firearms upgrades are a strategic leap toward enhanced performance, cost efficiency, and battlefield effectiveness.

The XM7, which began fielding in March 2024, marks the first time in 65 years that the Army is adopting a new individual weapon system to provide soldiers with the latest lethality, range, and accuracy advancements. 

Know the differences between XM7 and M4 here.

Is XM7 Replacing M4?

The U.S. Army’s fiscal 2025 budget request indicates a long-term plan to purchase 111,428 XM7 rifles, 13,334 XM250 automatic rifles, and 124,749 XM157 fire control devices. This plan to purchase the weapons extends into the 2030s.

This transition marks a significant investment in the future of infantry warfare, with the XM7 at the forefront of this revolutionary change. It is expected to offer enhanced capabilities against a broad spectrum of targets beyond the current capabilities of the M4. 

Despite introducing the new-generation rifle, the Army’s non-close combat forces will continue using the M4. It will remain a part of the Army’s arsenal for the foreseeable future.

The U.S. Army is progressively adopting the XM7 to allow for a gradual transition, providing time for testing, soldier feedback, and logistical adjustments. Meanwhile, the M4 is maintained in roles where its performance and features are still efficient.

Direct Comparison of the XM7 and M4

Here’s a direct comparison of the XM7 and M4 rifles, summarizing their key differences and improvements over its predecessor. 

The M4 Carbine’s legacy of reliability

The M4 carbine is a versatile firearm extensively used by the U.S. Army and Marine Corps. It’s lightweight, gas-operated, magazine-fed, and collapsible for easy storage. M4 was originally developed to improve maneuverability in urban combat and confined battlefields.

The M4 shares 80% of its parts with M16A2, but the M4 has a shorter 14.5-inch barrel and a telescoping stock to make it more compact. Over the years, the M4 underwent numerous improvements, including its ergonomics, modularity, and performance enhancements. 

The M4A1 variant, for example, has a fully automatic fire control group and a heavier barrel for prolonged automatic fire, particularly useful for Special Operations Command. Under the M4 product improvement program, enhancements such as a heavier barrel, a piston gas system, an improved trigger pull, and an enhanced rail system were also explored.

The M4 has been the primary weapon for many U.S. Army personnel since its first deployment in Kosovo in 1999. Its development replaced the M16A2.

Reasons behind the Army’s transition to XM7

The U.S. Army’s transition to the M7 rifle is a part of the Next Generation Squad Weapon (NGSW) program, aiming to improve the department’s infantry’s guns. In addition to replacing older rifles, NGSW includes creating new ammunition calibers and integrating advanced fire control systems. 

The XM7 rifle uses 6.8 mm bullets instead of the 5.56 mm bullets used in the M4 and M249 squad automatic weapons. This change makes the bullets more powerful, less affected by wind resistance, and more effective against enemies wearing modern body armor. 

Moreover, it is equipped with advanced optics and XM157 fire control systems. The fire control optics, made by Vortex Optic, have a laser range finder, a ballistic calculator, visible and infrared lasers, and a compass—all of which give soldiers precise aiming and tactical advantages. 

Other notable features of the new-generation rifle include ambidextrous controls, an AR-style charging handle, a left-side charging handle, a noise suppressor to conceal firing soldiers, and a two-position gas valve to adjust the amount of gas used to fire the gun. 

Meanwhile, the XM157 fire control systems can reach targets up to a distance of 1828 meters or 1.8 kilometers. These systems feature computer-aided ballistics, adjusting the distance and bullet drop automatically and enabling soldiers to engage targets more effectively at longer ranges.

While the M4 has proven to be an effective and versatile weapon system, the XM7’s advancements in ammunition, ergonomics, and integrated technology make it a formidable successor capable of enhancing soldier lethality. 

Read more: Squad Automatic Weapon: Redefining Infantry Power with Next-Generation Squad Weapons  

The potential impact of XM7 on future infantry tactics

The XM7 rifle is a weapon poised to influence future infantry tactics significantly. The 6.8 mm round can hit targets farther away and penetrate stronger enemy body armor. It enables soldiers to stay safer while still being effective in combat.

The rifle is also equipped with customizable features like rail systems for attaching accessories. It allows soldiers to adapt the weapon in different situations, such as thermal sights for night operations. While it is also heavier than the M4 rifle, the improved capabilities make it worth considering these changes.

In line with the XM7 rifle’s introduction to infantries, revisions to training programs and the development of a new doctrine to fully leverage its advantages began at Fort Campbell in April  2024. As soldiers become proficient with the weapon and its fire control system, the Army must also update its Tactics, Techniques, and Procedures (TTP) to incorporate these new capabilities.

Ongoing developments and upgrades of the XM7 rifle

Soldiers in the 101st Airborne Division tested the XM7 rifle and emphasized the forward weight where the noise suppressor (0.66 kg) was. They found that taking off the suppressor made the rifle lighter and easier to carry during long patrols. 

The Army and SIG Sauer are actively finding other ways to make the XM7 lighter.