Winchester NATO-Spec Army 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 situations significantly further than the selection of standard utilization. winchester 41 primers Winchester ensures thoroughly-managed weights of primer mixtures, regularity in dimensions and high-quality, specific measurements and tolerances for anvil heights and steadiness in extremes of temperatures and humidity.