Mosin accuracy

SuperJohn

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Hi all took my new mosin nagant 91/30 out yesterday for the first time. It's a 1940 round reciever, really nice shape. It tried some non corrosive mfs 185 grain. Mechanically the thing worked great, but gave m about a 10" group at 100 yards. Yes the trigger is rough so I was paying special attention to it. I can regularly group 2" or less with my iron sighted m14 so really don't think it's me. Everything on the gun seems tight. Any one have any suggestions? Oh, and the rifleing is very nice.
 
Throat erosion ?i had a 91 30 1944 bore looked good throat was shot out.do a col measurement, next id look into bedding,i wont even ask if action screws were tight
 
Been there done that with several Mosins and other milsurp rifles. Have the crown checked or re-crowned.


Did you slug the bore? what measurements did you get?
 
That trigger is a real SOB, I think the only one that's worse is the Nagant Revolver! There's a couple easy ways to shave a few pounds off that pull if you're semi handy with basic hand tools, check Youtube for some how to videos. Odd to have one shoot that poorly, even my wartime production with a somewhat rough bore shoots pretty well. I'd look to how the stock is bedded and check for any loose screws, etc...
* x2 on checking the crown as well.
 
Without a Bayonet they shoot kinda weird as well.
I was a doubter but it is true.
My M44 shoots better with the bayonet extended ( I feel a tad peculiar shooting with the spike out, but I don't shoot at the range anyhow)
 
Quick and easy way to lighten the trigger pull.

Mosin Trigger Job

M39 Trigger Job and Shimming the Receiver/Barrel End

Give these a read, and ensure that no hand guard or stock material is touching the barrel, except the last few inches. The Russians shimmed the receiver to tighten things up and put a greased felt wrap around the end of the barrel inside the stock to ensure upwards pressure. The barrels were not designed to entirely free float. Note the drawings to the right of the screen in article no.2 to see what I mean.

Also, slug your bore.

How to slug a bore.

The bore diameter in these rifles vary from .310 to .314 or so. Mine was .312, perfect for 150grn Hornady's of the same diameter. The Mosin, despite the crude sights is one of my most accurate shooters after doing these mods and tailoring my reloads to her.

Check the crown as well. If it's rough you can always order a brass crown lapping kit from Brownells. Should be about $15 or so. Google it! ;)
 
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As mentioned above check the action screws and bedding.

I have a feeling that the crown may be damaged as many mosin's are. If that is the case it may need a trip to the smiths for a counter bore.

If all of that stuff checks out it may just be that terrible trigger and the stout recoil?? I've never shot an m14 but if it's anything like a garand then I'd say it's a real pussycat compared to a mosin.
 
Thanks for the links Tyler, some great info there. As for the crown, I took a good look at the crown and it almost looks like there is a bit of a flat spot on the inside edge of the muzzle. I'm definately gonna get that looked at as well as the throat. I'd often wondered what there was to slugging a bore and that looks real easy. Thanks guys I'll let you know if I can improve it!
 
As for the crown, I took a good look at the crown and it almost looks like there is a bit of a flat spot on the inside edge of the muzzle. I'm definately gonna get that looked at as well as the throat.....



BINGO


I have a beautiful old Mosin that was shooting 10 inch groups at 25 yards. Forty bucks later for the re-crown, it was shooting 1 inch groups at 50. If your crown is not perfect, the bullet wobbles on exit.

Further to slugging, many Mosin barrels are cut over-size during wartime production. Every single Mosin I have shoots better with a .312 diameter bullet rather than the .310 surplus/factory diameter. Just FYI for what its worth.
 
I slugged two of my recent Mosin purchases. Both slugged out to .311 in near new barrels replaced at refurb, so I agree to find a projectile at .312 if you can reload. Crown condition is of paramount importance with all firearms as fiddler has pointed out, you can look up techniques to sharpen this up, it is quite simple to do. The bayonet extended definitely helps as the rifles were set up to shoot this way. You can also polish the sear contact surfaces on the bolt and trigger, this will take out the graininess out of the trigger. Unless you have a Finn take up spring in the trigger mech, once the bolt is cocked, there will be some slop in the trigger. Placing a brass shim between the trigger spring and the receiver, you can look up vids or stickies on this. Some guys have used felt saturated in boiled linseed oil to bed the rear tang area. There should be some vids or stickies on this as well. Good luck.
 
Personally I haven't had good accuracy with MFS ammo. I would try at least one different type of ammo before I was too alarmed. For example my son's SVT shoots like a shotgun with MFS and about 3" at 100yds with hand loads. My SKS shoots OK with MFS but better with everything else I've tried especially cast hand loads.
 
I had the same problem when I first started shooting with my 91/30 if I can tell you 2 things that I recommand for everybody is to recrown first of all!! A huge difference. and if you are willing to put 100$ in you mosin , go buy a timney trigger , best choise I've ever made !!
 
Never shot anything ten times.It's the first one that matters.These were out of the crate shot for groups...... not tuned in .......will do that to the pair I keep........... the rest will be sold....Harold
 
Hi all took my new mosin nagant 91/30 out yesterday for the first time. It's a 1940 round reciever, really nice shape. It tried some non corrosive mfs 185 grain. Mechanically the thing worked great, but gave m about a 10" group at 100 yards. Yes the trigger is rough so I was paying special attention to it. I can regularly group 2" or less with my iron sighted m14 so really don't think it's me. Everything on the gun seems tight. Any one have any suggestions? Oh, and the rifleing is very nice.

Probably all conditions described culminating for 10"s at 100 yards. Your marksmanship with the M-14 tells me your eye sight and basic marksmanship skill is not in question here, as is in alot of cases I see on the range.

The crappy trigger combined with that sight picture and the size of your bull for the distance, could put 4 to 5 " group's down for a rifle/shooter combo capable of 2MOA or less with more favourable conditions.

10 MOA is definitely bedding, tightness and/or throat/crown combined with the first two mentioned. Was there any indication of slight keyholing on target??

That MFS 185FMJ apparently is very accurate in my SVT40 at least. More to come on that one, if it wasn't just a flukey group day parade.;)

Good luck with finding out the cause,...I'm ready to pull the trigger so to speak on a Mosin91/30 to add to my fledgling tiny RedDawn collection, and it would be nice to know some of the barrel and accuracy issues with these refurbs. My SKS's and SVT were in excellent operational condition, the way you'd expect after an arsenal refurbed and packed them away to be "as good as new",.. in functionality at least for future use. I would have expected a Mosin to be a solid shooter right out of the crate!
 
I'm all for the d.i.y approach, and plan on the home trigger job. Also I also watched a couple of videos on crowning at home, looks pretty easy. If can get her to shoot with the irons then my plan is to go with some sort of LER scope set up. I'm gonna do every thing I can for it, my wife gave it to me for Christmas, and that was after she had said "no more shooting and hunting crap"! What a girl!
 
I just shot my sniper the other day for the first time, I got about a 3-4" group with it using surplus ammo at 100yds. My hex reciever Mosin through the iron sights wasn't that good, probably 8-10" group, but I'm sure thats partially due to my eyesight.
 
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