Winchester NATO-Spec Navy Primers 41 are a similar primers Utilized in the Lake Metropolis five.56mm ammunition. These primers are constructed to exacting technical specs for shot to shot consistency. All primers are regularly and rigorously examined for regularity and sensitivity at temperatures and disorders far over and above the choice of normal usage. Winchester guarantees very winchester 41 primers carefully-controlled weights of primer mixtures, consistency in dimension and good quality, exact measurements and tolerances for anvil heights and security in extremes of temperatures and humidity.