First developed specifically for use by US Navy SEALs in Vietnam, the first example of the Remington 7188, the Mk 1, appeared in 1967. Developed from the Remington 1100, the Model 7188 was a fully-automatic version of that weapon, with some other modifications requested by the SEALs like extended 8 round magazines, bayonet mounts, barrel shrouds and improved sights.

While the SEALs, particularly SEAL Team 2, liked the destructive power of the Model 7188 (especially with the custom N4 buck and flechette loads), they found the Model 7188 was highly-sensitive to dirt and fouling, and this made it quite unsuited for general use in Vietnam. In addition, the enormous recoil of a full-auto burst was difficult to control even at a slow 480 rpm, and even with an extended magazine, the ammunition supply was thought to be too small by many SEALs. There were never more than a couple of dozen of each version of the Model 7188 made, and they were withdrawn from service within a few years, a weapon experiment that ultimately failed.