Winchester NATO-Spec Military Primers 41 are the identical primers Employed in the Lake Town five.56mm ammunition. These primers are crafted to exacting technical specs for shot to shot regularity. All primers are constantly and rigorously analyzed for regularity and sensitivity at temperatures and disorders considerably further than the range of normal use. Winchester ensures thoroughly-controlled weights of primer mixtures, regularity in winchester 41 primers sizing and excellent, exact measurements and tolerances for anvil heights and stability in extremes of temperatures and humidity.