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 winchester 41 primers and situations significantly further than the selection of standard utilization. Winchester guarantees meticulously-controlled weights of primer mixtures, regularity in sizing and quality, specific measurements and tolerances for anvil heights and security in extremes of temperatures and humidity.