Winchester NATO-Spec Navy Primers 41 are the identical primers Utilized in the Lake Town 5.56mm ammunition. These primers are developed to exacting specifications for shot to shot regularity. All primers are consistently and rigorously tested for regularity and sensitivity at temperatures and circumstances far winchester 41 primers past the selection of regular utilization. Winchester assures diligently-managed weights of primer mixtures, regularity in dimensions and top quality, specific measurements and tolerances for anvil heights and security in extremes of temperatures and humidity.