Removing cosmoline from magazine


December 25, 2007, 10:13 AM
Okay, this section says "Keeping weapons in good order, improving functionality." (Nothing to do with "our" Cosmoline or the thread running elsewhere about "skanky" pink guns . . . :rolleyes: )
Anyway, I never encountered the preservative stuff before, even during eight years in the USAF. I had a pretty good idea what it was, though, when I started to peel a new Mec-Gar magazine out of its plastic bag.
I found the mineral spirits technique somewhere on the 'Net, and it seemed to work pretty well. The "obvious stuff" came off, but most of the mag now seems to have a matte finish to it; only the feed lips are a shiny blue. The four mags (also Mec-Gars) that came with my new SIG P226 have the same finish as the pistol, nice and smooth.
Did I get all the cosmoline off it, or does it need more "specs" and scrubbing? And am I going to have to disassemble the mag to remove the stuff from inside it?

If you enjoyed reading about "Removing cosmoline from magazine" here in archive, you'll LOVE our community. Come join today for the full version!
December 25, 2007, 11:06 AM
Generally that stuff is everywhere, I have found the best method is to soak in Kerosene at least over night if not for several days, then just pick out the parts. There are also several "cosmoline cooker plans" which I hear work pretty well for wood.

December 25, 2007, 11:23 AM
Cheap brake cleaner. Cuts right through the cosmoline, dries fast, and leaves no residue.

Can be done in just a few minutes.

December 25, 2007, 11:52 AM
Borrow your wifes Hair Dryer without her knowing it.

Or buy a cheap Heat Gun from Harbor Freight.

Take the mag apart and heat up everything except the spring until the cosmolene melts and runs off.

The rest is easily removed with a little solvent on a rag.
Use a cleaning rod & patches to get inside the mag body.

December 25, 2007, 12:14 PM
I usually have good luck with hot, soapy water... good dishwashing liquid.

December 26, 2007, 02:20 AM
Take the mag apart and drop it all into a tin foil roasting pan of mineral spirits for 24 hours. Then wipe off the cosmoline and re-oil. Just heating it will not clean all the cosmoline off. There will be a film of it left.

December 26, 2007, 02:52 AM
Boiling water with a little detergent here.

I f**king hate cosmoline!

December 26, 2007, 04:05 AM
Pressurized steam cleaner.

December 26, 2007, 11:16 AM
Pressurized steam cleaner.Oh, yeah, and a good vise to hold the mag while it's being blasted, or a big pile of rags in the opposite corner of the room. (For it to land in after the first shot of steam.) I bet that would get around any problem of how to depress the follower enough to clean the inside without taking it apart. :p
Actually, though, that does seem to be a good method, even without high pressure: (T)he carbine was caked in aging cosmoline that had taken on the characteristics of tile grout. :uhoh:
I hit the outside with steam and after about 5 minutes the cosmoline just dripped off into the large plastic storage bin. :cool:

Another site or forum had a discussion about cosmoline, and a link for a cleaner called Pro-Tek. I had recently seen something on Wikipedia about Coast Artillery men being called "Cosmoliners" because of their constant involvement with the stuff, so when I saw the little blurb for "Artillery Fungus" on the Pro-Tek page (, I thought sure it had something to do with gun guck. Nope, it attacks mulch, not howitzers. It's also called "shotgun fungus," but don't go fumigating your gun safe or anything. :p

I have some old toothbrushes stashed away for jobs like this. Time to break 'em out and see if I can make that magazine look shiny over its entire surface. Thanks for all the suggestions, guys.

December 26, 2007, 12:31 PM
I think I saw this formula before equal parts kerosine, transmission fluid, and mineral spirits.

December 28, 2007, 12:14 PM
I've had good luck with using boiling water and a rag to get 98% of it off of any part. The other 2% comes off with CLP, brake cleaner, or whatever solvent I have handy. My wife looks at me funny when I make repeated trips into/out of the kitchen with a 4 quart pot. :D

Nicky Santoro
December 28, 2007, 12:57 PM
I just put them in a container of appropriate size, cover completely with mineral spirits, cover, then let soak for a day or so. Go over them with a cheap natural bristle brush. Repeat if necessary. So far the best method I've tried. The good part is that the crap will settle out and you can use the MS over and over.

December 28, 2007, 05:39 PM
Slosh it in a bucket with a bit of gasoline in it for a great.

If you enjoyed reading about "Removing cosmoline from magazine" here in archive, you'll LOVE our community. Come join today for the full version!