Winchester NATO-Spec Military Primers 41 are exactly the same primers Utilized in the Lake Town five.56mm ammunition. These primers are constructed to exacting requirements for shot to shot regularity. All primers are constantly and rigorously tested for consistency and sensitivity at temperatures and problems considerably further than the selection of typical utilization. Winchester winchester 41 primers ensures thoroughly-managed weights of primer mixtures, regularity in dimensions and excellent, specific measurements and tolerances for anvil heights and security in extremes of temperatures and humidity.