Letter Re: Pre-1899 Finnish M39 Mosin Nagant 7.62x54R Rifles and Ammo

I read your novel, “Patriots” in 2003. It reinforced my survivor beliefs and encouraged me to take additional steps to become more prepared. I also enjoy reading SurvivalBlog.com and visit your site many times each day. Over the last six months I have followed your advice in purchasing three pre-1899 rifles. All three are Finnish M-39 Mosin Nagants chambered for 7.62x54R ammo.

I picked up one from AIM Surplus when [it was] first listed in December 2005. It appears to be in very good condition with a 1895 Tula receiver and 1944 SAKO barrel. The other two I purchased from gunsnammo.com which appear to be in mint condition – unissued, 100% blue, new bores, new post war stocks, matching bolts, unnumbered floor plates with a 1897 Ishevsk receiver and a 1944 VKT barrel. The other rifle has 1898 Tula receiver and a 1970 barrel.

I have spare parts, an Insta Mount from scopemounts.com, 100 stripper clips, and Forrester head space gauge and tools. The ammo I purchased from AIM Surplus: About 300 rounds of new Igman 150 grain jacketed soft point, brass case, boxer primed non-corrosive and 880 rounds of Polish 147 grain FMJ sealed in “spam” cans, made in the 1970s.

So far my knowledge of the M39 is based upon my Internet searches, an interesting ammo test posted at http://7.62x54r.net/MosinID/MosinAmmo.htm. and my current efforts to convert one to a sporter. Does anyone have any range experience with a pre-1899 Finnish M39 from AIM Surplus, gunsnammo.com or another dealer? Does anyone have experience with the specific ammo mentioned above? Jim, what are your thoughts, guidance, counsel on the M39s and ammo? – F.N.

JWR Replies: IMHO Mosin-Nagants are great guns that are both under-rated and under appreciated in North America. They have a tremendously strong action. Although I generally prefer the ergonomics, bolt style, and aesthetics of pre-1899 Mausers (such as those sold by The Pre-1899 Specialist), I still think that Mosin-Nagants are a good inexpensive choice for adding a pre-1899 to your survival battery. I don’t have any experience with the particular ammo that you mentioned, nor have I heard anything either good or bad about it. I’m sure that someone that reads the blog will offer an informed opinion about that ammo.

My main concern is that you get non-corrosively primed ammunition. For the sake of the newbies out there: There are essentially two types of rifle cartridge primers: corrosive (typically mercuric) that leave potassium chloride salts in the bore (with a strong affinity for moisture), and non-corrosive (typically lead styphnate) which leave no hydrophilic residue. Corrosive primers are a no-no unless you are absolutely scrupulous about gun cleaning. See this scholarly piece for a full description of the perils of corrosive ammo, and even the chemistry of the priming and residue. My general advice on military surplus ammunition, particularly from the former Eastern Bloc nations, is as follows: Unless you are assured in no uncertain terms that any particular batch of ammunition is not corrosively primed, then assume that it is corrosive. Don’t be fooled by advertisements that claim that their ammo is “mildly corrosive.” That is like a lass claiming to have been made “a little bit pregnant.”

The only way to be fully certain that ammo is non-corrosive is to use this priming test: First carefully pull a bullet and dump out all of powder from a cartridge. Then “blank fire” the cartridge’s primer at a piece of “in the white” unlubricated scrap steel from a distance of just one inch from the gun’s muzzle. (If need be, clean the scrap first with a degreaser such as Chem Tool..) Then leave that piece of steel exposed to the air for 72 hours. For those of you that live in a very dry climate, pick a fairly damp place such as your home bathroom for the test. Of course immediately clean the barrel of the rifle that you used for the primer test. If after 72 hours the steel test plate still has as uniform color and the center of the late has no more corrosion than the balance of the plate surface, then the primer was indeed a non-corrosive type. But if instead their is a rusty smudge in the center on the plate where the bore gasses impinged upon it, then the primer was corrosive. (Corrosive primers leave a hydrophilic residue, that induces rust.)

Unless or until you are certain that any particular batch of ammo is non-corrosive, then follow the standard U.S. Army pre-1900 cleaning drill, which is to thoroughly clean the rifle’s bore and bolt face for three days in a row, using bore brushes and bore cleaner. Otherwise, your rifle may end up with a badly corroded bore. To illustrate, here is a sad tale: I have a friend who will remain nameless that destroyed the bore on a mint condition Model 1909 Argentine Mauser. All that it took was one shooting session with corrosively primed ammo and then neglecting to clean the bore. Six months later, the bore looked like a sewer pipe.