The Mystery of the Inaccurate M39 Mosin

[Koobuh]

AIM's Superior Grade Finnish M39 rifles were simply too much for me to pass up. After a bit of hemming and hawing, I finally ponied up the $300+ they were asking to have a little piece of pre-WWII history sent to the FFL of my choice.

A few weeks passed (damned UPS and damned FFL), and it was at last in my hands.

So, we take it out shooting.
It was my understanding that the M39 could be considered the most accurate general-issue version of the Mosin. I've read rave reviews and amazing accounts, and with examples like my father's VZ-24/47 and M91/30 giving satisfactory results with surplus ammo, I had high hopes.

Only to be dashed.

The rifle handles well and has a nice trigger, yet the groups we achieved with it resembled buckshot patterns at 50 and 100 yards regardless of the ammo. Czech silvertip yielded the better results of the surplus, and Winchester FMJ made a pretty good showing with about a 6" group.
However, I'm still extremely disappointed in the 8"+ groups we were getting.

During the cleaning session I noted the brass shim plates that had been glued into the stock by the armory to increase accuracy. I also noticed that the barrel channel was enlarged to eliminate any wood to metal contact along its length.
The stock splice and date confirm that it is a post-war rifle, and should have no gremlins at all to work out.

Anyway, instead of buying some more Winchester FMJ and enjoying it as an 'OK' rifle, I'd like some suggestions to explain why this rifle isn't performing. The bore is absolutely beautiful, and the crown appears intact. As I mentioned, the trigger is nice (though I'll probably look into some coke-can shims when I do the other mosins), and overall the rifle itself is in very nice shape.
I'm considering hand-loads (Sierra Matchking 174 gr .311 dia HPBT bullets caught my eye) at this point too, so feel free to suggest some loads that might be worth trying.

Thanks, and for those interested, here is some more information about the rifle.

--
When I picked the rifle up, there were some huge dings in the stock. Naturally the FFL discarded the shipping box after opening it for logging so I couldn't see whether or not the dings were incurred during shipping or the rifle was that way to begin with. One of the dings is quite obviously from the sight of another M39, and there are some storage marks from the arsenal, but a couple of the gouges literally torn out wood. I'm hesitant to repair this myself, so they'll be staying for now unless someone can suggest a treatment.

Here is the information stamped into the barrel shank:

SA - capture mark
VKT - Valmet production mark
D - uses Russian/Finnish 'D' type ammo (basically standard stuff)
73255 - serial, and there is a strange reversed 'c' next to this
1944 - production date

I noted several more reversed 'c's on the bolt and have concluded that it's a proof mark of some sort, though what it means God only knows; I haven't seen it on the pages I checked. The bolt is a goldmine of markings; I noted an Izhevsk and Tula marking on the bolt body and cocking piece, as well as a bunch of other stuff that's eluding my understanding.

 

[R.W.Dale]

I'ed slug the bore on the rifle before I did anything else. In my opinion if you want to get a moisin to shoot this should be step ONE. Your M39 should have a .308 bore. The ammo you were feeding your rifle could be the result of your crummy accuracy.

Especally since my Moisin with a rotten oversized .313 bore shoots the winchester/S&B ammunition the best about 2.5 MOA

 

[Flyboy73]

Should get a C&R. For 30 bucks your M39 could have come right to your door. I got my M39 from AIM in 3 days after ordering. Love when the brown truck comes.

Still haven't cleaned or shoot the M39 yet. Working on my turkish mauser first.


Brion

 

[jobu07]

There is no reason why your M39 shouldn't be getting spectacular results with the dirtiest rottenest milsurp you can find to shoot through it (and even better results with handloads).

As suggested before, i'd try slugging the bore. Also, is the crown damaged at all? You say there are "proof marks" of mishandling. The imprint of another M38 sight to be sure. Perhaps someone was careless with a cleaning road at some point as well. My M39 is in terrific condition and shoots to match, however, a friend of mine has an M39 that was counter bored and again, shoots terrific. If the crown proves damaged you may look into that.

Or, as a final option, you may simply just ship the sucker back and say you're unsatisfied with it and would like them to send another. Either make it shoot or make them send you one that will!

 

[dfaugh]

A couple of observations, based on several Mosins, and other milsurps I've owned;

Check the crown VERY carefully. EVERY used milsurp I've bought had some cleaning rod wear at the muzzle, from using the issued steel cleaning rods. Unless it was unfired, there's probably (although possibly very minor) some problems there. but it doesn't take much at all to hurt accuracy. The only exception I've owned was a M-44 that had been re-arsenalled, and unfired.

I have never had milsurp ammo shoot well, and I've tried them all(7.62x54R, .303 British, 8x57). The Silvertip is probably the best I've ever seen, but still wasn't nearly as good as good factory ammo. I gave up on surplus ammo, for anything except making noise (and that's just to use up what I've got).

Your M39 should have a .308 bore.

Are you sure about this? I believe it should have a .311 (nominal) bore. But, if it slugs out much bigger than this, you'll probably have accuracy problems.

And, you simply may have an innacurate gun...No matter what type/model, these were mass produced, and weren't meant to be target rifles. They were only expected to shoot "minute of enemy" at reasonable ranges. I have a sporterized Turk Mauser w/ scope (original action and re-crowned military barrel) that shoots about 1 MOA, but otherwise most are in the 2-3 MOA range (although I have difficulty using iron sites due to vision problems. However, my buddy, with good vision, gets about the same results.)

 

[Ad Astra]

If that's superior grade, I'm a little surprised. AIM is my C&R favorite dealer, but the M39's I've gotten from WGA have been a better deal.

The pricey 1968 sneak from AIM shoots fine, and has a nice trigger but I think it was over graded a little, and I'm sorry to say that. Or the ones from WGA were undergraded. But the 1968's bluing wasn't as advertisied, and the rifle was full of dirt- actual Finnish soil- to my horror, when I took of its forearm and stock. ? I know the sneaks are somewhat rare, but WGA has them too.

For the same price (+50) I got an unfired-looking B barrel with new stock and hang tag from WGA. And it has a czarist eagle mark as well. Absolutely brand-new-ish M39. Cherry. Amazing, and well-worth it.

The 1941 VKT from WGA- I'm looking at it now. 100% bluing, good stock (some plugs) and a part-smudged eagle (now I know what to look for) and it was $199. Advertised as cracked forend; ridiculous. Unnoticeable hairline. And they all come with slings from there; had to buy one from TGP for the sneak.

All mine shoot great. Again, I like AIM best as a dealer, but WGA has some great rifles and they seem to (under)grade on the money.

You can fix your accuracy prob; too bad it's necessary. And was it dinged-up in shipping, who knows.

Get the C&R, and you'll know who wraps & ships well. And a 2nd mortgage and 2 more gun safes, they all go together.

As I recall, AIM does package very well. So does Classic and WGA.

 

[armoredman]

Mosin bores run .310 to .312 average. My freebie M38 gets 3.5 inch at 100 yards with Wolf ammo, so I don't know what happened with yours. I would try either slugging the bore for reloads, or returning it. Ditto on the C&R - paid for itself the first time I ordered a rifle.

 

[_N4Z_]

? link

can somebody put the WGA link up here? i'm shopping the C&R market and am not familiar with them.

 

[Ash]

If the crown is fine, which in M39's it generally is, you may need to re-shim the action. The m39 is regularly shimmed at the rear of the trigger guard and the front, where the two action bolts attach the action to the stock to the magazine. These shims serve to properly align the action in the stock and effectively free-float the barrel. If at some point the rifle were dissassembled and the shims fell out, accuracy could drop. Shimming wouldn't take much, but could be the real cause of your problem. If you adjust this with shims of your own, you could return the accuracy to this rifle (and discover just how accurate it really is).

The only Mosins to have .308 chambers were M28-30's and some earlier Finns, as a general rule. Every Finnish rifle with a "D" stamped on the barrel will be, as a rule, .310 and chambered for the Soviet standard round.

Ash

 

[Koobuh]

Ash, you are correct on the bore diameter, as far as I understand.

Re-shimming the rifle occured to me, as did slugging for actual bore diameter. At this point I'll probably give AIM a call to see what returning the rifle will entail, and go from there.
Thanks!

Also, C&R is a big nono for me. I have enough trouble paying the bills as is, and the safe is already overflowing from the family collection.

 

[Ad Astra]

WGA=Wholesale Guns & Ammo.

http://www.gunsnammo.com/

No C&R/FFL needed for these.

No, I don't work for them. I would get paid in M39's and lose my house.

 

[Kivaari]

M39

"During the cleaning session I noted the brass shim plates that had been glued into the stock by the armory to increase accuracy. I also noticed that the barrel channel was enlarged to eliminate any wood to metal contact along its length."

I've never noticed these shims to be glued into place and I've never noticed any of my M39's being fully floated either...most of the time there is some minimal pressure at the tip..albeit small. Perhaps someone "borrowed" some of the shims...

I'd check for a bent barrel (just in case) and barrel bulges, but I personally think its a bedding issue....front sight loose or something.....

 

[cracked butt]

[technical nitpick] If a mosin has a bore diameter of .308, .311, .310 or other diameters quoated in this thread, it can be considered wayyyyyyyy beyond shot out. If you are talking groove diameters, then you might be ok [/technical nitpick]

 

[Cosmoline]

Ash is correct. All M-39's (with the possible exception of the late models from the 60's and 70's) are .310"

M-39's are sometimes touchy beasts, and all Mosins seem to have certain ammunition they like and others they don't like. Your M-39 obviously doesn't care much for the limited range of ammunition you fed it. I would make sure your receiver screws are tight and try a larger mix. Most M-39's seem to like the heavy Wolf 200 grain loads, as well as D166 ball Lapua handloads.

Also, if you're not used to using iron sights that can have a big effect on accuracy. If you still can't get it to shoot straight PM me and I'd be interested in buying it off you at cost. I'd like to perform certain scientific experiments upon it.

 

[RON in PA]

SA is not necessarily a capture mark, it's the Finnish Army property mark. On a captured soviet 91/30 it does double duty, but on a new Finnish manufactured M39 it's just a property mark.

 

[Firehand]

With all mechanicals good, you should get good accuracy. With Czech silvertip, mine gets 1" at 100 yards when I do my part.

That being said, might try different brands, too; some rifles can be picky.

 

[hillbilly]

My M39 is ammo finicky.

When I use current production 200 grain ammo from Wolf, my M39 shoots bigger groups at 100 yards than it does at 300 yards with the Light Polish Ball (147 grain) stuff I got from Aim.

I mean at 100 yards, with the 200 grain stuff, my M39 shoots vertical strings that are about two inches wide, and about 14 inches tall.

At 100, with the Polish Light Ball, it's two inch groups or less.

Again if I were you, before you do anything radical to the rifle, I'd get my hands on at least two more types of ammo and shoot it off a bench first.

hillbilly

 

[Cosmoline]

The touchiness of the M-39's is one reason I currently favor other Finnish models. I think the committee made a mistake on insisting that they switch to a heavy pistol grip style stock. Making the stock thicker has actually led to MORE cracking over time, not less. And it causes a lot of problems with barrel interference. Hence the mass of shims one usually finds underneath the actions.

Another thought along these lines--TAKE OFF THE HAND GUARD! It takes about a minute and helps ensure that over-tight bands aren't the cause of the problem.

 

[Koobuh]

Okay, so I tried some of the yellow-tip 174 gr Hungarian heavy ball, and got somewhat more satisfactory results.
I managed to get six of eight shots in the black on a standard target (8" bull) at 200 yards.

I'll probably end up working some on the shims, but I think I found the bullet weight it likes... just really wish it had liked something lighter. My arm's killing me.