Winchester NATO-Spec Military Primers 41 are the identical primers Employed in the Lake Town 5.56mm ammunition. These primers are created to exacting technical specs for shot to shot consistency. All primers are consistently and rigorously analyzed for regularity and sensitivity at temperatures and conditions much over winchester 41 primers and above the number of regular utilization. Winchester ensures meticulously-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.