As anyone who has had any dealings or run-ins with Surplus already knows the first major hurdle to over come in the area is Cosmoline. Now, most people you may talk to take issue with cosmoline. It smells, it is sticky, it is waxy, it gums stuff up, it melts onto your hands while you are firing, etc. While all of these are true, trust me it has taken me over a week to get that smell off my hands and arms before, the thing to remember is that it is great at doing it’s job: protecting your little piece of history from rust and aging while it is being stored. After seeing so much hatred for the foul stuff I decided to write a post about what it is, what it does, and most importantly good and safe ways to remove it from your firearm.
So, what is cosmoline? The most important thing to know about cosmoline is in fact it’s intended use and that is as a rust preventative. That being said the actual name “cosmoline” is really just a generic term for rust preventative, usually these agents range in color from brown to orangeish, greasy gel to waxy substance, and dirt smelling to petroleum smelling. Perhaps the most important thing to know about cosmoline is that it begins melting around 110 degrees. The appearance of cosmoline will change depending on whether or not it has been exposed to oxygen, which is also a good way to tell about the storage conditions of the firearm you are about to purchase. While cosmoline is fresh or has been sealed away from oxygen it will provide a very greasy and jelly-like substance that just reeks of petroleum product. The longer cosmoline is exposed to oxygen the more it starts to coagulate and create more of a waxy solid that will crust over parts of the firearm. This means that if you go to purchase a firearm and it has a waxy crust it has been out of it’s original packing for some time, greasy and jelly means they were likely just taken out of original packaging. Cosmoline was used for it’s ability to coat every single surface and action of a firearm. This was great for preventing the rusting that can easily be found in surplus firearms that were not coated with cosmoline or hermetically wrapped.
Why do you need to know about cosmoline? Simple, if you are seriously interested in Curio and Relic and surplus firearms you will have to wrestle with this sticky substance many times. Whether you are buying your firearms from Cables, online (whether through transfer or with a C&R license), or at a mom and pop shop, almost every surplus firearm will come with a thick coating of it. Cosmoline is perhaps most notoriously used on former Soviet-bloc weapons but can easily be found in American, German, English, Chinese, Turkish, and many other weapons as well. Finding cosmoline on a weapon should not be something that drives you away from it, rather something that makes you inspect it more closely. You may have to look closer at a gun with cosmoline to be able to see everything, but you do not have to worry about internal rusting near as much as you would with a surplus firearm you found without any cosmoline on it. Cosmoline can also make it infuriating to check an action, especially with semi-auto weapons, as it will gum up the action and lock it back (or lock it have opened or close). If this happens just keeping pulling and pushing the bolt/charging handle until it frees up some. Cosmoline can also make it hard to check a barrel for rifling as it has a tendency to fill up a barrel and block it off from light. If this becomes an issue for you at a gun store do not let it stop you, walk up to the proprietor or a clerk and ask if they have something you can push through the barrel. I have done this many times and have ended up with a cleaning rod with some solvent on it, fixes the issue and you have taken your first step towards cleaning your gun. So the main lesson is this: do not allow cosmoline to frustrate you or prevent you from purchasing the firearm you want, it does it’s job and does it well.
There is one problem with cosmoline: it does it’s job too well. Cosmoline will get in every nook and cranny of your firearm. This is a huge hazard especially in semi-automatic firearms. Cosmoline will attract fouling and dirt which will gum up the firing pin and action in your SKS, AK, M1 Garand, M1 Carbine, etc. This is dangerous, because as time goes on it makes it more and more likely that your firing pin will stick forward and fire full-auto uncontrollably (AKA slamfire). Slamfires are incredibly dangerous. If the person handling the weapon is not expecting it you can lose control of the aim and fire in unsafe directions, just the muzzle climb can launch ammo to maximum ranges. Why did I tell you this? I assure you it was not to scare you, rather to clean and lubricate your firearms as often as possible. Before you bust out your Hoppe’s 9 and get ready to clean your C&R or surplus firearm like you do your other guns, you have to really clean them first. The first thing you will need to do with any C&R or surplus firearm is to completely disassemble it. I mean completely, remove the action from the stock, take the receiver apart, bolt assembly apart, if necessary the piston, the bayonet, all of it. This is particularly easy to do with Soviet-bloc weapons, most of them have limited moving parts, and were made to be maintained by relatively uneducated Serfs that were conscripted to fight for the empire or working people for the Party. Quick side-note: if you have a punch-pin that is sticky, DO NOT hit it with a hammer or punch, put a towel or felt on it and then apply pressure. Alright, once everything is stripped apart go ahead and take your stock and set it off to the side, we will get to that later. First, you will need to procure some things. You will need a large plastic or metal tub, it needs to be big enough to fit your entire barreled action in it. You will need a solvent, I have used Kerosene and WD-40 in the past (yes WD-40 worked to remove cosmoline from a Nagant Revolver), but you can use Simple Green and other less harsh products as well…you just need a whole lot of it. During the first and second World Wars soldiers would use Diesel and soapy hot water to remove cosmoline as well, I have never tried it and I doubt that I will given the success that I have had so far. It helps to have some stiff brushes and wire bore-bits laying around to help clean the tough stuff off. You can use a toothbrush or you can buy some cleaning brushes from a gunstore or mechanics shop.
Now that you have everything together, put metal parts in the tub and pour enough solvent in to cover them. Now, people differ in opinions as to what to do from here but usually I will let them soak for at least 20 minutes before picking up pieces and scrubbing them off. From this point you will need to check the parts about every 20 minutes and scrub the tough spots, once the solvent clouds or changes colors dump and refill it. You will need to repeat this process until the pieces are clean, then you will set them aside to air dry. While your moving pieces are drying it is a good time to get to work on the stock, hand guards, etc. The first thing you can do with your wood components is to do your best to take a paper towel and wipe them down to soak up any extra cosmoline. Once you have done this you can proceed several ways, you can use a hair dryer to heat up the stock, put the pieces out in the sun, or put the parts in a photo-absorbant container (IE black bag) and put them in the sun. I live in Texas, which makes this choice real easy…I just put them in the sun for a couple of hours. Any route you go, you will be looking for the same thing: Cosmoline heats up enough that it will make a greasy layer on the stock. Once you get the cosmoline to rise to the surface of the stock you wipe it off and repeat the process, you can do this as much as you want until you feel done. Now that you have cleaned everything go ahead and reassemble the weapon and open the bolt. Your weapon should be pretty clean but just for kicks I always run a couple of patches with Hoppes on them down the barrel before running a couple of clean ones to dry it up. The last step you need to take, even if it is a brand new gun, is to go ahead and apply a light coating of RemOil or the like to the metal components…this will help prevent rusting (you should also do this after anytime you shoot the weapon). Once everything is cleaned up go ahead and fire a round or two just to make sure everything works, then run a patch again.
Keeping your firearm in clean working order should be done with all arms, but any owner of a semi or full-auto firearm should be that much more vigilant. Keep in mind that with a bolt action you cannot have a slam fire, setting off a chain reaction, only semi-automatics. Maintaining your firearm with prolong it’s effective life and if you plan on shooting and collecting, keep it’s value up. If your firearm begins to secrete some more cosmoline after you fire it some, no worries this happens a few times then it will stop. Hopefully this has helped you out some, if you have any more specific questions like what products I use or how to clean a certain arm go ahead a leave me a comment; I will get back to it.
Stay Safe and Keep Shooting