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View Full Version : Accurizing a Mosin-Nagant



Josh Smith
12-22-2011, 02:36 AM
Hello,

The Mosin-Nagant tends to be an inherently accurate design as illustrated by the Finns. Problem is that most were poorly executed by the Russians as precision was not high on the priority list. Here's a brief look at what I like to do to mine!

The first thing you want to do is smooth the barrel channel using an appropriate sized dowel rod or socket from a ratchet wrench, wrapped in 320 or so sandpaper. When you are done, you should be able to lay a straight edge along the barrel channel.

http://i19.photobucket.com/albums/b191/WabashShootist/Mosin%20Nagant/Accuracy/barrelbedding.jpg
Lightly oil the cork bedding on both sides.

Next, cut cork, lay it in, and lay the barreled action into the stock. Observe whether the barrel lays flat. It may. Now, tighten the front and rear screws to about 50in-lbs. The barrel will probably raise the muzzle quite a bit.

http://i19.photobucket.com/albums/b191/WabashShootist/Mosin%20Nagant/Accuracy/rearshim.jpg

http://i19.photobucket.com/albums/b191/WabashShootist/Mosin%20Nagant/Accuracy/frontshim.jpg
Bring lots of ammo and tools to the range. This takes a lot to get right.

Start placing cork material in the front and rear. You want the barrel to lay as flat as possible when the action screws are tightened.

On mine, I could not get the barrel to lay perfectly flat, as there is an as-yet undiscovered pressure point someplace in front of the front action screw. It raises just a little bit.

http://i19.photobucket.com/albums/b191/WabashShootist/Mosin%20Nagant/Accuracy/handguardshim.jpg
I used business card stock on the top handguard. Oil it well.

This is not necessarily a bad thing though. It provides an opportunity to add another known pressure point.

http://i19.photobucket.com/albums/b191/WabashShootist/Mosin%20Nagant/Accuracy/slingessentials.jpg
Move the front sling mounting point back!

And this is critical: You have made the barrel bed and handguard one with the barrel. You have a heavy barrel now, for lack of a better term. It's bad for harmonics when you attach anything to the barrel, so move the sling back, especially if you are like me and use the sling to shoot!

Have fun!

Regards,

Josh

cevulirn
12-22-2011, 09:00 AM
Seems your pictures got a little out of place?

I'm familiar with cork bedding, but I've never done it. Have any thoughts on bedding with Acra-glass?

Schuetzenman
12-22-2011, 10:36 AM
Seems your pictures got a little out of place?

I'm familiar with cork bedding, but I've never done it. Have any thoughts on bedding with Acra-glass?

I've done a lot of bedding with Acra-glass Gel, works good. I've also found that some of these old military weapons do well if suppored well at the breech end of the barrel and up by the muzzle and left free-floated in between so they can shake-rattle-n-roll more uniformly.

BTW, nice post Josh.

Rainman
02-11-2012, 03:23 PM
The Finns use steel shim stock in the areas indicated. Put a few thou in until it's straight and solid. Once you have the shims in place and correct, use a tac nail to secure them so you don't loose them when you field strip. That is the Sako and Valmet method....Works like a charm. Old school charm that is.

A way to tell right off if you have barrel/stock tension is to tighten the back screw first then the front. If the front gets "tight", then continues to tighten further, that is tension, and will affect your accuracy and means you need a few thou in the REAR. That front screw should set, then tighten no more than 1/2 turn to the proper torque setting. This is true for both single and dual screw take down bolt guns. If that screw gets tight and keeps turning under pressure, you're putting tension on something and that aint good. Always use the same procedure and torque when reassembling.

Hope this helps

Rainman