Machine Gun With Longer Reach Sought By U.S. Army

Yahoo

12-03-2025

The U.S. Army is looking at acquiring a new machine gun chambered to fire the .338 Norma Magnum cartridge, but that can also be converted to use the same 6.8x51mm ammunition as its next-generation M7 rifles and M250 light machine guns. A machine gun in .338 Norma Magnum would give Army units much greater reach than they can get now with their 7.62x51mm M240-series types. The service is eyeing conversion kits that would allow its existing M240Bs and M240Ls to fire the 6.8x51mm rounds, as well.
The Army's Contracting Command-New Jersey at Picatinny Arsenal recently issued two separate contracting notices seeking information about potential options for a dual-caliber .338 Norma Magnum/6.8x51mm machine gun and M240B/L 6.8x51mm conversion kits.
The Sig Sauer MG 338 seen in the video below is one .338 Norma Magnum machine gun on the market now.
'The dual caliber machine gun should include all hardware and instructions needed to operate as a .338 Norma Machine Gun and the conversion kit to fire the 6.8x51mm XM1186 general purpose cartridge,' the notice regarding that weapon states.
'Presently, the M240B and M240L machine guns are 7.62[x51]mm weapons. The durability, reliability, and function of the M240 weapon platform cannot be significantly compromised with a change in ammunition,' the conversion kit notice says. 'The conversion kit should include all hardware and instructions needed to modify a standard M240B and M240L to fire the 6.8mm XM1186 general purpose cartridge. This will include a new barrel assembly and may include changes to the weapon powering through updates to the gas regulator, drive spring, or other means. The barrel assembly must be the standard barrel length (M240B) and short barrel length (M240L).'
M240s are the Army's current general purpose machine guns. The B model, with its roughly 24-inch long barrel and 27.6 pound unloaded weight, is the baseline type in the service's inventory today. The lighter weight L version, with its shorter barrel (just under 22 inches), collapsible stock, and titanium receiver, tips the scales at 21.8 pounds. The Army also has a M240H variant with spade grips instead of a buttstock for use as a helicopter door gun.
The Army currently issues M240 variants for use by infantry and other dismounted personnel, as well as in vehicle and helicopter-mounted applications. M240s are also in widespread use elsewhere across the U.S. military in similar roles, as well as mounted on ships and small boats.
The main benefit of acquiring a new machine gun in .338 Norma Magnum would be the additional range such a weapon would offer over 7.62x51mm M240s, as well as improved terminal effects on targets at those longer distances. .338 Norma Magnum has historically been more of a caliber option for sniper rifles.
The Army's stated maximum effective range of an M240B against an area target is 1,312 yards (1,200 meters). That shrinks to around 875 yards (800 meters) when talking about engaging specific point targets, according to manufacturer FN. A .338 Norma Magnum machine gun could offer at least double the effective range, if not more, depending on the design and specific ammunition loadings.
Being able to relatively readily convert any new machine gun to fire the 6.8x51mm round would also offer valuable ammunition commonality with the M7 rifle and the M250 light machine gun. 6.8x51mm ammunition is also lighter and cheaper per round than .338 Norma Magnum, which could be beneficial, especially for routine proficiency training on shorter ranges. The ability to convert M240B/Ls to fire 6.8x51mm would provide similar benefits to the Army.
It is worth noting here that the U.S. special operations community, at times in cooperation with the U.S. Marine Corps, has been actively working toward adopting a .338 Norma Magnum machine gun for the better part of a decade now. U.S. Special Operations Command (SOCOM) was reportedly expected to issue a formal request for proposals for what it has been (somewhat confusingly) calling a Lightweight Machine Gun-Medium (LMG-M) by the end of last year, but it is unclear whether or not that occurred.
SOCOM and Marines have already been evaluating multiple .338 Norma Magnum machine gun designs in recent years. This includes Sig Sauer's MG 338, the design of which is directly related to the M250 light machine gun that the company is already supplying to the Army. Sig Sauer is also the manufacturer of the M7 rifle. Sig Sauer has notably also shown a version of the MG 338 with spade grips for vehicle and helicopter-mounted applications, as well as an example of standard versions of the gun in a naval mounting, in recent years.
MG338's spade grip enters production. Tool-free conversion from flex mount to an infantry-carried gun in a single assembly. pic.twitter.com/AyMhFtFlpB
— Gregory Knowles (@2805662) October 9, 2023
SIG Sauer MG338 twin mount shows off it's alternate left/right feed & left/right charging handles. Also shown is the 7.62 NATO calibre exchange kit, primarily intended for training. pic.twitter.com/vOtNTGql7b
— Gregory Knowles (@2805662) October 10, 2022
As part of its LMG-M, SOCOM is known to have tested at least two other .338 Norma Magnum machine gun designs, what is now branded the RM338 from True Velocity and Ohio Ordance Works Recoil Enhanced Automatic Rifle (REAPR). The RM338 began life at General Dynamics Ordnance & Tactical Systems as the Lightweight Medium Machine Gun (LWMMG).
Talk about caliber conversions for existing M240s as a tangent to the Army's adoption of its new slate of 6.8x51mm guns is not new, either.
Large-scale adoption of a dual-caliber .338 Norma Magnum/6.8x51mm by the Army could aid SOCOM in its ongoing push to field such a weapon and lead to its use elsewhere within the U.S. military and help spreading out of associated cost burdens. Similarly, M240s firing 6.8x51mm ammunition could see wider-spread use if the Army moves ahead with those plans. U.S. military small arms procurement trends often have global impacts, as well.
The Army is already in the midst of a major small arms shift with its new M7 rifles and M250 light machine guns, and now a new general purpose machine gun may be closer on the horizon.
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