"Designed in 1961 by Carl Benson, the Mossberg 500 was created mainly for use by hunters, but quickly found itself in use by law enforcement because of its reliability and low cost.[2] In the 1970s, the M500 was submitted for military use, but failed to meet the MIL-SPEC 3443E protocol,[2] which involves firing 3,000 rounds of shells with no more than two malfunctions.[3] During the testing, some M500s were created to better match the MIL-SPEC, which came at an increase in cost.[2] M500s began to be purchased by the US military in limited numbers, with the first order consisting of approximately 5,900 shotguns for the Navy and Coast Guard"