The US Army has to rename its new rifle after accidentally using the name of another gun

• The US Army is changing the name of its new rifle after accidentally taking a name from another gun.
• The Army's M5 from Sig Sauer will be called the M7 because Colt already makes a rifle called the M5.

The Army is changing the name of its new rifle after accidentally taking a name from an unrelated existing weapon, the service announced Wednesday.

The service's upcoming M5 from Sig Sauer will now be called the M7 after it was discovered Colt Industries also makes a weapon called the M5. The light machine gun set to replace the M249 Squad Automatic Weapon, or SAW, the M250, will not change.

"The Army originally chose the designation XM5 as the name of the new rifle in March," a service spokesperson said in a statement. "Since then, the service learned that the M5 name is used by Colt Industries for one of its 5.56mm carbines."

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The new weapons have an X designation to indicate they have not yet been fielded. The weapons' capabilities, including how far they can accurately engage targets, are unclear as the Army is still testing them.

But it'll be roughly a decade before most formations see the M7 or M250. The service plans to issue only a small batch of roughly 40 weapons this year, with more expected to trickle out as the Army builds new ammunition factories to accommodate the new type of bullets required for those firearms. Production on the new ammo isn't expected to kick off in any significant way until at least 2026.

The new weapons use 6.8mm rounds as the Army looked for heftier ammo than the current 5.56mm used in the M4 and SAW to better defeat body armor, protective equipment that adversaries are expected to have in future conflicts and gear that is already becoming more commonplace for terror groups. The 6.8mm was seen as a compromise between the light ammo currently used and the 7.62mm ammo used in the M240B machine gun that would be very heavy for a standard rifleman.

Army planners are already bracing for that heavier load from the new ammo and expect soldiers to carry less in the next fight. The M7 weighs 9.84 pounds, much heavier than the 6.34-pound M4. Soldiers will also use 20-round magazines, a 10-round decrease from the magazines the Army has been using for decades. A standard combat load for the new rifle is expected to be 140 rounds, a sharp drop from the 210-round loadout for the M4.

Soldiers carrying the new light machine gun will have a break, with the M250 weighing 14.5 pounds, compared to the 19.2-pound SAW. But troops are expected to carry only 400 rounds of the heavier ammo, a steep decrease from the standard 600-round load for SAW gunners.

The new weapons are part of the Army's larger long-term plan to modernize its force by 2030, with service leaders aiming to update its formations so that they're ready to fight a conventional military, a change from the last two decades of combat as part of the Global War on Terror era. Some of those efforts also include investments into new vehicles, robotics, long-range missiles and upgraded air defense systems.

"Most of the doctrine we use and the weapon systems are late '70s, early '80s, that we've incrementally improved," Gen. James McConville, the Army's top officer said at an Association of the US Army event Wednesday. "We're taking a look coming out of Iraq and Afghanistan, and we need to be ready for large-scale combat operations."

— Steve Beynon can be reached at [email protected]. Follow him on Twitter @StevenBeynon.

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