Analysis and technical review about the new Heckler & Koch M110A1 Squad Designated Marksman Rifle (SDMR), which started to enter in service with United States Army. In April 2016 Heckler & Koch confirmed that a lighter version of the G28 (derived from the MR308/MR762, which is based on the HK417) had won the U.S. Army's Compact Semi-Automatic Sniper System contract to replace the M110 Semi-Automatic Sniper System under the name of M110A1.
Heckler & Koch M110A1 Squad Designated Marksman Rifle (SDMR) at AUSA defense exhibition in Washington D.C., October 2017. (Picture source Army Recognition)
On April 4, 2020, Heckler & Koch Defense Inc. has announced the first shipment of M110A1 Squad Designated Marksman Rifles (SDMR) to the US Army. This shipment is the first of many that will eventually total between 5,000 and 6,000 complete weapon systems.
The M110A1-based rifle will replace the M14 EBR, in use by the Army since 2009, but because it was based on an operational needs statement it had to be turned in by units at the end of a combat deployment.
M110A1 Squad Designated Marksman Rifle (SDMR): in March 2018, the Army announced that a version of the G28/M110A1 would be issued to infantry squads as the service's standard Squad Designated Marksman Rifle (SDMR). Issuing a 7.62×51mm NATO SDMR is meant to increase individual squads' ability to defeat enemy body armor that standard 5.56×45mm NATO rounds cannot penetrate.
A product of extensive customer input, the HK Squad Designated Marksman’s Rifle is a modified, improved version of the Heckler & Koch G28 rifle. Offspring of the Compact Semi-Automatic Sniper System (CSASS) competition which HK won with the M110A1 in April 2016 — the SDMR model is essentially the same weapon except for a handful on different features.
This new HK rifle is a lightweight variant of the combat-proven 7.62 mm G28 in use by the German Army. The M110A1 capitalizes on the proven G28 design, meeting user requirements for accuracy, reliability, and size. The M110A1 rifle is a substantial upgrade over current sniper rifles, enhancing accuracy and reliability while providing for a handier, more compact arm.
The M110A1 uses a short-stroke gas piston to actuate an operating rod which allows the weapon to run cooler and with less fouling of the bolt carrier group and chamber — drastically improving reliability. Pioneered by Heckler & Koch in the G36, HK416, and HK417; this method of operation virtually eliminates malfunctions common to direct impingement gas systems since hot carbon fouling and waste gases do not enter the receiver area.
The M110A1 stays cleaner, reducing heat transfer to the bolt and bolt carrier, and drastically reducing wear and tear on other critical components. The service life of all parts is increased substantially. The M110A1 has a 16.3-inch (41.402 cm) barrel that is chrome lined with a fluted chamber that aids in reliability when used with a suppressor. The barrel is produced by Heckler & Koch’s famous cold hammer forging process. This manufacturing process uses the highest quality steel, producing a barrel that ensures superior accuracy, even after firing thousands of rounds.
The controls and interface of the M110A1 are similar to M4/M16-type weapons, ensuring operator familiarity and simplifying training. Ambidextrous operating controls are standard on the M110A1, including a convertible charging handle, as well as selector levers and magazine releases located on both sides of the lower receiver. The HK M110A1 variants have some significant differences from standard Heckler & Koch G28/HK417/MR762 type rifles.
The M110A1 uses a Geissele designed slim-line, M-Lock compatible handguard. The HK M110A1 departs from the traditional black weapon color and uses a tan-brown color scheme analogous to “flat dark earth” — the finish also has special low IR observable properties and is camouflaged for many environments. There are several weight reduction features on the system, including lighter adjustable buttstocks, lighter bipod, lightening reduction cuts in the castle nut, barrel nut, handguard, and upper receiver. The AR-style forward assist is also eliminated. M110A1 rifles without optics, suppressors, and accessories weigh in at 8.8 pounds (3.99 kg). The M110A1 has ambidextrous controls, an improved trigger, and uses an updated one piece OSS suppressor.
The M110A1 uses the same 10- and 20-round translucent polymer box magazines made for the HK417, G28, and MR 7.62 mm rifles. And the HK M110A1 can be fitted with a wide variety of accessories and options.
