In 1967, Hathcock set the record for the longest sniper kill. He used an M2 .50 Cal Browning machine gun mounted with a telescopic sight at a range of , killing a Vietcong guerrilla. In 2002, this record was broken by Canadian snipers (Rob Furlong and Arron Perry) from the third battalion of Princess Patricia's Canadian Light Infantry during the War in Afghanistan. Hathcock was one of several individuals to utilize the M2 Browning machine gun in the sniping role. This success led to the adoption of the .50 BMG cartridge as a viable sniper round.