7.62 x 53R (or x 54R)

[Bad Flynch]

Just bought a collector-grade Finnish Mosin Nagant M39. It is one of the batch made in 1967 through 1973. The importer lists them as "match rifles," but the Finnish sources state that they were made for officer marksmanship training. This one, made in 1967, is probably unfired and still has the arsenal hang tag attached to it. It was made at the Helsinki Arsenal. It is a nice gun, but it is still ugly.

What brings this up is that the Finns rifled and chambered their rifles for .308 diameter bullets up to WWII. At that time, they saw the problem with Russia coming and switched over to a .310-.311 groove and bullet diameter so the rifles would function with captured Russian ammunition. Many of the older rifles were rebarreled to the new dimension and some were merely opened up in the neck. This one has a .311 groove diameter and shoots .303 caliber bullets quite well. Nowadays in Europe, the .308 diameter round is designated "x 53R" and the .311 diameter round is designated "x 54R." In the U.S. the terms are interchanged freely, so slugging the barrel of your Mosin is in order.

All of the American die manufacturers of which I am aware, make reloading dies suited for .308 diameter bullets. Nevermind that all of the rifles coming in now, Russian and Finn, take .311 diameter bullets. Brass is expensive (as in Lapua brass) and simply changing the expander ball to .303 works, but overworks expensive brass.

I just called Forster, asking them if they made a die suited to the larger bullet. Forster is one of the few makers to produce dies for small cartridge dimensional differences, e.g., they make both .308 Win and 7.62 x 51 mm (called "National Match") dies. What is really neat is that they offered to open up the neck on my standard die for a measly $10.00 and replace the expander ball. I ordered a complete new die on the spot. Nice to find a manufacturer that understands our needs.

Credits: www.mosinnagant.net for most of the stuff.

 

[Langenator]

The RCBS 7.62x54R die set comes with two expanders, one .308 and one .311.

And it may be too late for you for this batch, but Graf's has their own less expensive brass than Lapua from any source I've seen.

 

[Koobuh]

"It is a nice gun, but it is still ugly."
You take that back.
The M39 is the best looking production Mosin-Nagant. So there.

Langenator is right, you can get dies that will expand the neck to the correct diameter.
If you feel like duplicating the ammunition this rifle was built to fire, build a cartridge with Lapua brass and D-166 bullets with Vihta Vuori rifle powder.
The Lapua brass is sometimes designated 7.62x53R, and some people comment that it's a bit shorter than standard cases. Supposedly the Finns measured the case length differently than the Russians, but eh.

Really, you don't have to try very hard with these rifles. They are very accurate for a general issue service rifle, and can shoot acceptably even with cheap milsurp. I'm consistently getting 2-3 MOA out of my '44 VKT with Hungarian yellow-tip ball ammo, which was made for use in machine guns. That's pretty darn good for a Mosin with surp ammo.

A lot of people will still use .308 diameter bullets in their Mosins with good results, so don't feel like you MUST use .311 or higher bullets. This is a situation where experimentation is suggested.

 

[DaveInFloweryBranchGA]

After you've developed a load for the gun and shoot it a time or two, it'll get prettier. It'll reward you for your effort.

Kinda like an average looking woman with a great personality that takes good care of you if you treat her decent. Pretty is is pretty does, as my Momma used to say.

Glad to hear you were able to get the dies set up as you wanted, in the brand you were interested in.

Regards,

Dave

 

[lee n. field]

All of the American die manufacturers of which I am aware, make reloading dies suited for .308 diameter bullets.

My RCBS set has both .308 and .311 expanders. Lee has a .311 expander available for theirs.

 

[Clark]

I have an M39, some 91/30s, and some M44s.
I have the RCBS dies and the Forster dies.

My M39 chamber can get so tight with .311" Sierra and .312" Hornady bullets that the pressure goes way up and makes a sticky bolt, difficult extraction, and very high velocities, in what should be a medium load.

The bullets will not fit in the fired cases, so the chamber neck is tight.

I have a Manson 7.62x54R reamer with floating pilot, that I could use to make the M39 take normal ammo, but I think I will experiment with .308" bullets.

 

[Bad Flynch]

Well, here is some follow-up:

The barrel is as slick as a powdered baby's butt. It does not metal foul when I shoot it, and that with 174 grain Hornady solid point bullets. I cannot wait to get it on paper, but that will have to wait until after Christmas. Nice experience, so I ordered a Russian M91/30 with a laminated stock. SOG has them on sale and the condition is Excellent plus, and I ordered special selection. My salesman always leans on them to "get it right." too.

>Graf's has their own less expensive brass than Lapua <

Thank you a bundle, I was just going to order some S&B loaded ammo to glean the cases for reloading. Now to Graf's. I can even have a different brand for the Russian rifle to keep them separated.

>The Lapua brass is sometimes designated 7.62x53R, and some people comment that it's a bit shorter than standard cases. Supposedly the Finns measured the case length differently than the Russians,...<

Yes, my brand-new out of a box of 100 Lapua cases are very short. It will be a while until I have to trim them. The Lapua cases are stamped x 53R, too.

>The bullets will not fit in the fired cases, so the chamber neck is tight.<

I have no trouble whatsoever with sliding a bullet down in, but we'll see as time goes on if .308 diameter bullets will shoot--dimensional differences notwithstanding.

 

[Langenator]

No prob. Something I discovered a bit later than I'd have liked.

 

[Bad Flynch]

>Yes, my brand-new out of a box of 100 Lapua cases are very short. It will be a while until I have to trim them. The Lapua cases are stamped x 53R, too.
<


to get to the bottom of this, I did a little snooping around and here is what I found: The original case length of this thing was something like x 53.5R. Being that, some European countries rounded it up (to x 54R) and the Finnlanders rounded it down (to x 53R). That system prevailed until the 1930s when Europe standardized and the cartridge became the x 54R, especially for the cartridge with the larger bullet. Not so for the Finns, who preferred the .308 bullet and the x 53R case designation.

I measured my Lapua (x 53R) brass, and it is just about the length you would expect for a 53mm case; that is, about 0.020" shorter than the nominal case length for the x 54R. Maybe that is where the short Finn cases get their dimensions.

 

[gezzer]

Same cartridge different names

 

[Cosmoline]

I've had no trouble getting both .308" and .311" expanders from Lee.