US Army's New Machine Gun Will Fire at Tank Gun Pressures

The current issue Squad Automatic Weapon (SAW) will be phased out by a firearm capable of defeating armored targets at range.

The FN M249 SAW
The FN M249 SAW will be phased out by a more powerful light machine gun with a greater range.photo from foxnews.com

According to reports, the U.S. Army will replace the current issue M249 Squad Automatic Weapon (SAW) with a firearm that fires rounds at significantly higher pressures and speed.

Citing increasingly armored opponents, the Army is borrowing technology already found in its Abrams A1 tanks to increase downrange effectiveness in its automatic weapons. And thanks to recent advances, the whole package will be lighter than the existing M249’s 17 pound heft, FoxNews reports.

The Army is shooting for a weight of 12 pounds.

Ammo is also expected to be 20 percent lighter and to be telescoping ammo, a new kind of technology the Army has been flirting with that uses polymer cases instead of brass. The reduced weight should increase troop mobility, according to a story by Fox News.

Specifications for the new weapon call for chamber pressures between 60 and 80 KSI (kilopound per square inch)—the same as the main gun on a M1 Abrams. Most combat weapons operate around 45 KSI, for comparison. Distance, accuracy, and lethality will be increased thanks to this higher pressure.

FN M249 Squad Automatic Weapon
The FN M249 Squad Automatic Weapon (SAW) has been in service since 1984 and fires belted 5.56 NATO ammo. It is also capable of using STANAG magazines from M16 rifles and M4 carbines.photo from wikipedia

The current 5.56 NATO M249 SAW has been effective in battle against unarmored combatants, but recent threats from countries with advanced defense programs have created a need for a more powerful light machine gun, the story says.

Called the Next Generation Squad Automatic Rifle (NGSAR), Fox News says the Army aims to replace 80,000 M249s with the new weapon as soon as 2022.

The story, which exaggerates the potential effectiveness of the platform just a bit, says the NGSAR will have a rate of fire of "60 rounds per minute," which is most likely an error. The cyclic rate of the SAW is 650-800 RPM, so the article most likely meant 600 RPM. The story also says the NGSAR will be capable of touching off 3-round bursts for 15 minutes without a barrel change or malfunction.

Textron Systems has been tasked with creating a working prototype of the NGSAR. The company aims to create a magazine fed, intermediate caliber firearm based on their existing Cased-Telescoped weapons and ammunition.

The story doesn't say what ammo the NGSAR will use, but that will be the most important detail.