They mean corrosive. As in ammunition with corrosive primers. After yesterday’s blogger shoot Borepatch Son #2 helped out by spraying down my two MilSurp rifles with ammonia based window cleaner. What makes corrosive ammunition corrosive is actually the primers. Older military (and civilian for that matter) ammunition used Mercuric Salts which when moist will attract significant amounts of moisture to the gun. Moisture makes metal things rust, and guns are no exception to this. Modern ammunition uses non Mercury primers, so is not a problem. Well at least in theory, but anything coming from former Soviet Bloc nations or China is suspect, to me at least.

Ammonia will neutralize the salts and therefore stop potential corrosion. Other people prefer WD-40, but most sources I’ve read or talked to say Ammonia is the way to go. You can use Windex or any generic cleaner as long as it has Ammonia in it.

Anyway, back to my story. When I got home from yesterday’s shoot, I was pretty worn out. It was a lot of fun, but with the travel, set up, shooting, talking, clean up, and so on, it made for a long day. I unpacked my truck, moving five long guns, five hand guns, three ammo cans formerly full of ammunition, my range bag, cleaning kit, and some other stuff to the basement. Then I unpacked everything and put it where it belonged. I decided to take a shower, eat, and then go to bed. I would do the gun cleaning today, since I wasn’t working anyway. My basement is pretty dry, so I wasn’t worried about corrosion. Silly me.

I did my modern, non military long guns first. The 10/22 is pretty easy to clean, as are the Savage 69RXL and the Marlin 336C. Then the SMLE No1. MkIII. No problem with that either, young Borepatch Son #2 did a good job spraying down the barrel, action, and even the magazine. Some Hoppes #9, followed by Breakfree, followed by M Pro 7, cleaned everything up. Probably a bit of overkill, but better safe than sorry.

Then the SKS carbine. I removed the recoil spring cover and the spring itself. I figured that I’d just have to remove the bolt carrier and bolt/firing pin and give it all a quick clean up. Ooops, wrong. There was corrosion, not much, but definitely enough to need some attention on the bolt, bolt carrier, magazine well, chamber. I did a complete field strip and cleaned the crap out of the rifle before putting it back together.

The sooper seekrit range we were at was fairly deep into the woods, where it was warm and extremely humid. Which is when the moisture crept into the rifle. I then put the rifle into a hard case and closed it, likely trapping the moisture inside. I then left the closed case closed when I got home, making things worse.

Lesson learned. Next time, take off the recoil spring cover and remove the bolt carrier and bolt. THEN spray the whole thing down with Windex or some other Ammonia based cleaner.

Just so I’m clear, this was a failure on my part and in no way reflects on the fine effort of Borepatch Son #2 in cleaning up my rifles.

I got away easily and learned my lesson without undue damage to the rifle. I’m posting this to my fellow MilSurp shooters so they will be forewarned. My guess is that this is more of an issue with a semi automatic than a bolt action, but that’s just a guess.