The gun was developed as part of a project called TDP 3801 during the 1960s, and much of the work on it occurred at the Naval Surface Warfare Center White Oak Laboratory in Silver Spring, Maryland, US.
It proved effective but, says Tom Hawkins of the nonprofit Naval Special Warfare Foundation, "It was bulky and heavy and the men never warmed up to it.
It was also a signature controlled item – as in signing your name to check it out – and administratively a burden to the operational units.
The distinctive cartridge fired by the M1 is the Mark 59, a stainless steel cylinder containing a single 4.25-inch (108 mm) long heavy tungsten dart.
The self-contained design of the Mark 59 contributes to the propellant gases being kept in the cartridge, which eliminates muzzle blast that could produce a dangerous shock wave.