M4 Vs. Enhanced M4A1 Standard

Key Differences Between The M4 & The M4A1 Standard

Adopted in the mid-90s, the M4 was conceived as a lighter and more maneuverable platform to replace the iconic M16 rifle. The original variant could be fired in semi-automatic or burst-fire modes, while retaining many of the cosmetic features of its predecessor - a carry handle, front sight post, and distinctive two-piece handguard.

Later models would ditch the carry handle in favor of a Picatinny rail mount on top of the receiver. Gradually, lights and laser modules became standard kit for infantry and handguards began to incorporate rail panels (and eventually, M-LOK slots) for attaching accessories.

The Next Evolution Of The Modern Fighting Rifle

The M4A1 introduced several additional improvements, such as a heavier barrel for improved accuracy and full-auto fire instead of the original M4 carbine's three-round burst. Additionally, updated models were more modular and could be adapted for a variety of mission parameters. Quad rail handguards with rail covers became the norm, allowing a much higher degree of customization in regards to accessory placement and compatibility with foregrips, infrared lasers, etc.

Essentially, the M4A1 took everything that worked well with the M4 and made it even better. Troops gained the ability to suppress and engage enemy combatants more effectively without compromising their CQB readiness when negotiating tight, confined spaces. Plus, improved modularity allowed the M4A1 to be reconfigured into a Designated Marksman Rifle or a squad support weapon with the iconic M203 underbarrel grenade launcher.

Why The U.S. Army Is Converting More M4 Rifles To The M4A1 Configuration

In addition to enhancing infantry troops' combat efficacy, the M4A1 is much easier to field and maintain from a logistics perspective. This one platform can be adapted to perform specialized roles that were previously filled by several different rifles, which simplifies training and reduces the number of replacement parts that armorers must keep on hand to keep the M4A1 in good working order.

Converting existing M4 carbines to the updated M4A1 configuration is also less expensive than purchasing brand new rifles, and still achieves the military's goal of expanding each soldier's capabilities before the new XM7 rifle is adopted across the board.

Sig Sauer MCX Spear-LT Semi-Automatic 5.56x45mm Ambidextrous Rifle, 16" Barrel, 13" M-LOK Handguard, Side Folding Stock - Coyote Brown Finish - RMCX-556N-16B-LT
Sig Sauer MCX Spear-LT Semi-Automatic 5.56x45mm Ambidextrous Rifle, 16" Barrel, 13" M-LOK Handguard, Side Folding Stock - Coyote Brown Finish - RMCX-556N-16B-LT
Be the first to know when this product is back in stock!

How To Train With Your Rifle & Pistol

Of course, training is just as important as the tool you use. Watch our video to learn how to train with your AR-15 and sidearm more effectively and put your skills to the test.

Shop all AR-15 style rifles!