Winchester NATO-Spec Military Primers forty one are precisely the same primers Employed in the Lake Town 5.56mm ammunition. These primers are crafted to exacting specifications for shot to shot regularity. All primers are frequently and rigorously examined for regularity and sensitivity at temperatures and conditions considerably outside of the range of normal utilization. Winchester assures thoroughly-managed weights winchester 41 primers of primer mixtures, regularity in dimension and high quality, precise measurements and tolerances for anvil heights and security in extremes of temperatures and humidity.