Winchester NATO-Spec Armed forces Primers 41 are the exact same primers used in the Lake Town five.56mm ammunition. These primers are constructed to exacting specs for shot to shot consistency. All primers are consistently and rigorously examined for consistency and sensitivity at temperatures and winchester 41 primers situations much over and above the variety of usual utilization. Winchester guarantees carefully-managed weights of primer mixtures, consistency in sizing and high-quality, exact measurements and tolerances for anvil heights and balance in extremes of temperatures and humidity.