[2] The SDM-R is similar in development and role to the SEAL Recon Rifle and Mk 12 Special Purpose Rifle (SPR), designed and produced for the United States Navy SEALs and the United States Special Operations Command respectively.

[3] The addition of an embedded marksman at the platoon or squad level has historically been a continuing process in the U.S. military.

The SDM is not meant to be a squad sniper who engages the enemy with precision fire at long ranges, but instead is trained to directly support the squad with well-aimed shots at ranges slightly beyond the normal engagement distances for riflemen.

The SAM-R has since been replaced in U.S. Army service, mostly due to the performance of match grade 5.56 NATO ammo in the DMR role.

[1] Its slated replacement was the Heckler & Koch HK417-based M110A1 SDMR,[6] expected to enter service in the early 2020s.