Winchester NATO-Spec Armed forces Primers 41 are exactly the same primers Employed in the Lake Town 5.56mm ammunition. These primers are built to exacting specifications for shot to shot consistency. All primers are constantly and rigorously tested for regularity and sensitivity at temperatures winchester 41 primers and disorders far further than the variety of regular utilization. Winchester assures very carefully-controlled weights of primer mixtures, regularity in dimension and good quality, exact measurements and tolerances for anvil heights and security in extremes of temperatures and humidity.