Here's What You Need to Remember: While the M110 was originally procured as a semi-automatic replacement for the M24 sniper rifle by the U.S. Army, it has been used successfully in the designated marksman role as well. In USMC service, it replaced the M39 EMR and M14 DMR as a designated marksman rifle, both variants of the original M14. In Army service, it replaced various versions of the M14 EBR.
The designated marksman rifle is becoming increasingly popular in recent years.
The United States is purchasing more of them through the Army’s Compact Semi-Automatic Sniper System (CSASS) program. Also, in a recent reform of infantry equipment, the British Army announced that it would be ditching its version of the M249 SAW, the L110 Minimi, and buying more L129A1 designated marksman rifles.
What rifles could be considered the best for this role?
1. Knight’s Armament Company M110
While the M110 was originally procured as a semi-automatic replacement for the M24 sniper rifle by the U.S. Army, it has been used successfully in the designated marksman role as well. In USMC service, it replaced the M39 EMR and M14 DMR as a designated marksman rifle, both variants of the original M14. In Army service, it replaced various versions of the M14 EBR.
Based on one of Eugene Stoner’s last designs when he worked for Knight’s Armament Company (KAC), the SR-25. The SR-25 (Stoner Rifle 25) is an update of the original AR-10 updated with elements of the AR-15, hence the “25” in the name is based on adding the 10 and 15.
At the time of adoption, the M110 featured advanced ergonomics for an AR rifle. It had an ambidextrous bolt catch and safety for ease of off-hand manipulation and faster reloads.
While the M110 is said to be on the chopping block to be replaced by the new H&K CSASS, U.S. Special Operation Command’s recent adoption of the 6.5 Creedmoor as a long distance round may extend the service of the M110. Versions of the M110 chambered in 6.5 Creedmoor were tested as SOCOM’s next DMR/sniper rifle in March 2018.
2. H&K SDM-R (M110A1 CSASS)
While the M110 was a successful program, the U.S. Army wanted a smaller and lighter version to be easier to carry and fit in with squad more. The procurement of a M110 replacement was run under the moniker of M110A1 Compact Semi Automatic Sniper System (CSASS). While KAC submitted a shortened version of the M110, the H&K G28 (a variant of the HK417) won the contract.
While the original M110 was used in both the designated marksman and sniper roles, the Army decided to split the CSASS program into two different rifles, the CSASS meant for snipers and the SDM-R meant for designated marksmen.
The difference between the CSASS and the SDM-R is in the type of ammunition they are meant to use and the scopes mounted on the rifle. The CSASS mounts a 3-20x Schmidt and Bender optic and is optimized for M118LR sniper ammunition. The SDM-R mounts a 1-6x Sig Tango Low Power Variable Optic (LPVO) and is optimized for the use of standard M80A1 ammunition. The 1-6 Sig Tango features an integrated bullet-drop compensating reticle that allows for faster, albeit less precise shots, as the scope isn’t meant to be “dialed” in like the more powerful Schmidt and Bender optic.
While old and obsolete compared to most other rifles on this list, the Soviet SVD can be considered the original designated marksman rifle. While the name includes “снайперская винтовка,” which literally means “sniper rifle,” the Soviet conception of sniping is far closer to the Western designated marksman than the Western sniper.
The SVD has proven itself to be reliable, rugged, and accurate since its adoption in the 1960s. The PSO-1 scope was the best designated marksman scope in the world when adopted, featuring a ballistically matched elevation adjustment out to one thousand kilometers, and a simple windage adjustment. In contrast, most western scopes were set to a fixed zero at the time. It also featured an advanced infrared light detector, although this feature began to be of dubious utility as the West phased out infrared spotlights on their night vision equipment.
The SVD continues to see use in many countries around the world today.
Like the M110, the L129A1 is a variant of the AR-10 meant for use as a designated marksman rifle. However, the design features custom upper and lower receivers made by Lewis Machine and Tool (LMT). During British trials for a designated marksman rifle, the L129 beat out the FN SCAR, other AR-10 offerings (albeit, not one from KAC) and the HK417.
The L129A1 proved wildly popular with British troops in Iraq and Afghanistan, being one of the highest rated weapons used by troops. It’s one of the only Urgent Operational Request (UOR) weapons from Iraq and Afghanistan that has outlived its temporary nature and has gone onto be an integral part of the British rifle squad.
5. FN SCAR
The FN SCAR has also seen significant use in designated marksman roles across various militaries. While FN offers specialized sniper variants of the SCAR, the common standard length SCAR has found to be suitable to performing designated marksman roles.
In American service, only SOCOM uses the SCAR in a designated marksman-type role. In SOCOM usage, the SCAR is usually topped with a 1x/6x or 1x/4x ELCAN optic, which feature bullet drop compensating reticles.
Like the M110, the SCAR was tested in 6.5 Creedmoor as a potential candidate to become SOCOM’s next semi-automatic sniper/designated marksman rifle.
Charlie Gao studied Political and Computer Science at Grinnell College and is a frequent commentator on defense and national security issues. This piece was originally featured in August 2019 and is being republished due to readers' interest.