Military corrosive ammunition dating Xxxdating oc ca
The potential for bore corrosion and accuracy reducing pitting and rifling erosion caused by chlorate primers is real, but it is readily mitigated by immediate and proper cleaning after a shooting session.
Upon firing, the potassium chlorate in the primer becomes potassium chloride, a salt, which deposits the length of the bore.
Again, especially in humid climates, it is important to clean immediately after a session of shooting with potassium chlorate primers.
But this isn’t typically possible in a combat environment, so the military’s search for a non-hygroscopic replacement for potassium chlorate was on soon after they hit the streets.
These had zinc plated primers; the zinc intended to protect the primer cup from reacting with a component in the noncorrosive primer mixture.
Since these few FA lots were small and remain unidentified, the post-1950 cautionary rule still stands.
The Ammo Encyclopedia (6th Edition, 2017, Michael Bussard) has information slightly differing from Harrison’s, stating Frankford Arsenal utilized chlorate primers “until the mid-1950s.” Another researcher has done us a service in publishing a paper that specifically identifies noncorrosive US manufactured military ammunition from WWII to 2001, including .30-06, 45 ACP and 7.62 NATO, by lot number and date; a free, downloadable PDF is online at: odcmp.org/1101/
” Most recently, the question posed to me was in regards specifically to military surplus M2 Ball .30-06 brass.Water was the “secret” ingredient in bore solvents ever since potassium chlorate primers hit the scene in the 1890s, but it only works if the shooter cleans soon after firing.Anyone who has polished brass fittings on a ship knows that salt water will tarnish and dull brass.Mercuric primers pose a problem to handloaders in that once fired, the mercury amalgamates with the brass and causes it to become brittle.If such a case survives its trips through a sizing die, it may eventually fail upon firing.
Noncorrosive primers finally became standardized for the US military in 1949, and by 1950 all US military small arms ammo, including newly manufactured M2 Ball (and that was our original question, wasn’t it?