Army Testing New XM8 Carbine (No, Not That XM8)

Some members of the U.S. Army will begin receiving a new XM8 carbine for testing in October 2026, a shorter, lighter version of the M7 rifle introduced under the branch’s Next Generation Squad Weapons (NGSW) program. The carbine version was developed by SIG Sauer as part of its joint Product Improvement Effort with the U.S. Military. The gun received the official XM8 designation and stock number from the U.S. Army in March, according to Soldier Systems.

The XM8 trims one full pound off the M7’s 8.3-pound heft. Its shorter barrel contributes to the weight savings, along with modifications to the upper receiver.

“The XM8 is just over 32 inches long overall, compared to 37 inches for the M7, with a barrel length dropped from 13 to 11 inches and its suppressor from 7 to 6 inches,” SIG Sauer product manager for rifles and suppressors Joshua Shoemaker told Task & Purpose. Other enhancements include a handguard that’s more rigid and softer recoil pad.

Its 6.8x51 mm chambering remains identical to its big brother and the M250 Automatic rifle, which was also introduced with NGSW. The XM8 wears a telescoping buttstock, rather than the M7’s side-folder.

Complete adoption of the M7/XM8 platform by all branches of the U.S. military is not in the near future, however, if ever. “The Marines have decided to stick with the M27 Infantry Automatic Rifle instead of switching to the Army’s M7 Next Generation Squad Weapon Rifle,” a spokesperson for the branch told Task & Purpose in February.

The new carbine’s label has fueled some confusion among those who remember Heckler & Koch’s submission for U.S. military trials earlier this century. It was also dubbed the XM8 for testing, but the guns are unrelated and do not share the same chambering.

A story about that H&K submission appeared in American Rifleman in 2005, and explains, in “October 2003, the first 30 were sent to Aberdeen, Md…This modular family was first built and tested in the 5.56x45 mm, but it can also easily be adapted for the new Remington 6.8 mm SPC.”