The Same 20-Inch Barrel, A Lighter Package

The M110A2's action is gas-operated and semi-automatic only, an AR-10/SR-25-pattern derivative built around a rotating bolt, the same basic mechanism as the base M110 it upgrades¹. Knight's Armament did not shorten the barrel to save weight. The M110A2 keeps the same 20-inch (508mm), 1-in-10-inch-twist, 5R-rifled match barrel as the original M110, machined from ORD 4150 steel in a dimpled hybrid medium profile and left free-floating². Muzzle velocity and effective range therefore carry over directly from the base rifle, roughly 2,571 ft/s (784 m/s) with M118LR ammunition and a published effective range out to about 1,000 meters on point targets, though these figures are inferred from the base M110's published performance rather than a separate M110A2-specific test, since the barrel and chambering are unchanged³. Knight's Armament markets the M110A2 with the same core mission statement used for the original M110, built to deliver precision fire on point targets past 1,000 meters, underscoring that the upgrade is about ergonomics and weight rather than a ballistic redesign².

M-LOK Rail, Folding Stock, and Ambidextrous Controls

Where the M110A2 actually differs from the base M110 is in furniture and controls. The continuous top rail of the original M110 gives way to a roughly 12-inch M-LOK-compatible handguard, which KAC calls its Universal Rail Extending (URX) system, a free-floating design that trades some rail-mounting surface for lighter weight and more flexible accessory placement^1,2. The fixed stock of the base rifle is replaced by an adjustable, folding, collapsible stock, cutting several inches off the rifle's overall length when folded and bringing total length down to a range of roughly 39.9 to 44 inches (101 to 112cm) depending on stock position, versus a single fixed length on the original M110^1,3. Bolt release, safety selector, and magazine release are all fully ambidextrous, giving left-handed snipers the same handling as right-handed shooters, a change the original M110 never had³. The detachable magazine system is unchanged, still feeding from the same 20-round SR-25-pattern box magazines used across the whole M110 family³.

Suppressor and Trigger

The M110A2 adds a new, KAC-made integral suppressor, addressing a compatibility problem that reportedly dogged the rival Heckler & Koch G28-based rifle and contributed to that program being fielded mostly as the unsuppressed SDMR rather than the sniper-role CSASS⁴. Trigger geometry stays a two-stage match design, with a light take-up first stage and roughly a 4.5 lb pull on the second stage². None of these changes touch the optic. The M110A2 uses the same optics family fielded across the M110 program, originally the Leupold Mark 4 LR/T 3.5-10x40mm and later the Leupold Mark 5HD 3.6-18x44, which the Army selected for the M110 line in 2020⁸.

From a 2016 Contract Loss to a 2022 Amendment

Knight's Armament had actually lost the Army's original 2016 competition. The service picked Heckler & Koch's G28-based CSASS submission that April, intending it to replace the M110 across the force⁷. KAC itself submitted a competing upgraded-M110 candidate during the pre-decision test process, field-tested by Fort Carson's 2nd Infantry Brigade Combat Team in 2019, when eight Army snipers fired roughly 8,000 rounds through it in the Rocky Mountains under cold-weather and Ghillie-suit conditions¹⁰. That 2019 KAC submission was an earlier, separate candidate from the finished M110A2 product, and the CSASS name it competed for ultimately went to the Heckler & Koch design instead¹⁰.

Despite losing that contract, KAC kept a separate, ongoing five-year, $13 million Army deal (2020) to keep supplying standard M110 SASS rifles¹. Because most of the Heckler & Koch M110A1 rifles that actually reached troops were built as the squad-level SDMR rather than the dedicated CSASS sniper variant, the Army still needed a modern, dedicated-sniper 7.62mm rifle years after the 2016 decision⁶. Knight's Armament answered that gap in-house, folding an upgraded M110 configuration, the M110A2, into its existing contract rather than competing for a new one¹.

First Public Debut and the Best Ranger Competition

Knight's Armament unveiled the M110A2 publicly at the AUSA annual meeting in October 2021, in an Army-specific configuration¹. The rifle's first documented use outside a trade-show floor came several months later, at the US Army's Best Ranger Competition at Fort Benning, Georgia, held April 8 to 11, 2022¹. A Ranger-qualified soldier from the 101st Airborne Division fired the M110A2 during a course that included three moving and eight static targets, immediately after a physically demanding preceding event, a setting built to test both the rifle and the shooter under fatigue rather than a combat engagement¹.

No confirmed combat deployment of the M110A2 has appeared in open-source reporting as of this writing. That is a real and notable gap for a rifle that has now been under Army contract since 2022, and it stands in contrast to the base M110 it replaces, which built an extensive documented combat record in Iraq and Afghanistan after its 2008 fielding³. That earlier combat history belongs to the original M110 rather than the M110A2, since the newer rifle did not exist during those deployments, and it should not be read backward onto the upgrade.

The M110 SASS, fielded from 2008, is the predecessor the M110A2 upgrades and the rifle whose ballistics and basic action the M110A2 keeps unchanged³. The M110A2 itself is Knight's Armament's own in-house refresh of that rifle, adding the folding stock, M-LOK rail, new gas system, and new suppressor described above^1,2.

Two further, unrelated variants carry the confusingly similar M110A1 name and come from Heckler & Koch rather than Knight's Armament. The M110A1 Compact Semi-Automatic Sniper System (CSASS) is the dedicated sniper-role rifle that won the 2016 competition outright, built on the HK417/G28 platform, fitted with a Schmidt & Bender 3-20x50 PM II Ultra Short scope, and weighing about 8.40 lb (3.81 kg) unloaded⁴. The M110A1 Squad Designated Marksman Rifle (SDMR) is a separate program built from the same HK417 base but issued to squads rather than dedicated snipers, fitted with a lower-power SIG Sauer TANGO6 1-6x24 variable optic instead of a fixed sniper scope, weighing about 9.15 lb (4.15 kg), with fielding aimed at roughly 6,000 units completed by late 2023^4,6.

Knight's Armament also still sells M110-family rifles commercially, including an M110 SASS Limited Edition Deployment Package, generally following the original M110's configuration rather than the A2 upgrade².

The United States Army is the M110A2's only confirmed operator so far, fielding it to dedicated sniper teams under the amended 2022 contract, with the 101st Airborne Division the only specific unit documented using it in open sources, via its entrant at the 2022 Best Ranger Competition¹.

No confirmed Marine Corps, Air Force, or US Special Operations Command adoption of the M110A2 specifically has been found. SOCOM's own parallel precision-rifle interest, reflected in a 2022 procurement document about 6.5mm training ammunition, centers on a separate 6.5mm evaluation rather than adoption of the 7.62mm M110A2⁹. Because open reporting on the rifle is still limited to its 2021 unveiling and 2022 competition appearance, the scale of its fielding across the wider Army sniper community beyond the 101st Airborne is not clearly documented and should not be overstated.

The Army's dedicated-sniper role that the M110A2 now fills has been served by a series of earlier 7.62mm rifles going back decades, the Vietnam-era M21 Sniper Weapon System, its accurized M25 Sniper Rifle refinement, and the more recent M38 Designated Marksman Rifle conversion of the M14. None of those older rifles remain in first-line Army sniper-team service today, but each established the same institutional requirement, a semi-automatic 7.62x51mm NATO precision rifle for Army snipers, that the M110 family and now the M110A2 continue to fill.

The clearest rivalry for the M110A2 sits inside the US Army's own inventory, against its Heckler & Koch-built stablemate, the M110A1 CSASS. Both rifles were built for the exact same dedicated-sniper role, effectively splitting that role between two manufacturers after the 2016 competition. The CSASS undercuts the M110A2 on paper weight, 8.40 lb (3.81 kg) unloaded against the M110A2's 9.92 lb (4.5 kg), and it runs a short-stroke gas piston rather than the M110A2's direct-impingement-derived action, a difference that generally favors the piston gun for running cooler under sustained fire^2,4. The M110A2 answers with a longer, unchanged 20-inch barrel (the CSASS is shorter) and a new integral suppressor that avoided the mounting problems reported on the G28-based rifle, problems that pushed most Heckler & Koch production toward the unsuppressed squad-level SDMR instead of the sniper-role CSASS⁴.

That table also shows why comparing the M110A2 to the SDMR is a role mismatch rather than a fair fight. The SDMR carries a 1-6x24 low-power variable optic built for fast target transitions at squad ranges, not the fixed, high-magnification sniper scopes both the M110A2 and the CSASS use, and it was issued roughly six times over (about 6,000 units against a far smaller M110A2 buy)⁶. A unit deciding between the two KAC-versus-HK dedicated-sniper rifles today is really choosing between an updated, more familiar AR-10-pattern action with unchanged 20-inch ballistics, or a lighter, piston-driven HK417-based rifle with a shorter effective package. Neither has a confirmed unit price published, so cost is not currently part of that comparison in any sourced way^1,5.

What is the difference between the M110A2 and the M110A1 The M110A2 is built by Knight's Armament Company as an upgrade of the original M110. The M110A1 name covers two separate Heckler & Koch rifles instead, the sniper-role CSASS and the squad-role SDMR, both built on the HK417/G28 platform rather than the M110A2's AR-10-pattern action⁴.

What caliber does the M110A2 fire The M110A2 is chambered in 7.62x51mm NATO, the same round used by the base M110 it upgrades, fired from an unchanged 20-inch match barrel^2,3.

Is the M110A2 still in service Yes. Knight's Armament has supplied it to the US Army under an amended contract since 2022, with the 101st Airborne Division among the confirmed units that have used it¹.

How much does the M110A2 cost No official per-unit price for the M110A2 has been published. The original M110 SASS cost $11,214 per the Army's FY2013 budget documents, and the rival Heckler & Koch G28 was reported around $12,000 per rifle at the time of the 2016 contract decision, but neither figure isolates the newer M110A2's own unit cost¹.

What is the effective range of the M110A2 Because the barrel and chambering are unchanged from the base M110, the M110A2 carries the same published effective range of roughly 1,000 meters on point targets, though this figure is inferred from the base rifle's specifications rather than a separately published M110A2 test³.