I recently acquired a 7.62 Mosin Nagant. I'm a little confused about the bullet diameter. I've loaded for the 7.7 Japanese Arisaka with a Hornady .312" dia. bullet, the same bullet that the .303 British uses.

Privi-Partizans are probably about as authentic as they get and they are .311". I see that some bullets are are even .310".

The most available (I think) for me is the .312" Hornadys.

Which bullets in the .310" to .312" range are right for the Mosin Nagant???

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"He was kinda funny lookin'"

Annoying enough, the answer is the ones that shoot the best for you. The Russian built Mosins can have groove diameters that range from 0.309" to 0.314". (Throw, if you want, in the Finns who decided to use 0.308" grooves for a while.) Not a huge drama with open base bullets typically used, but it can take some experimenting to find solid base bullets that will be quite so tolerant.

Slug your bore.

There were 40 MILLION Nagant rifles made often under wartime conditions and usually to a low standard of quality. They vary in bore's diameter.

Only then will you know what pills to feed your communist boat anchor.

I've loaded for 7 or 8 rifles in 7.62x54R. In my experience use Norma brass and the largest diameter bullet in that family. Be sure to get the weight that is for the country of origin's ammo (usually 174 grain works in everything, but the POA won't match the POI)

WWI guns are now over 100 years old and WWII guns are almost 75, try loading to the correct velocity but with a powder that generates the lower pressures.

I also like 175-190 grain cast bullets, sized .001 or .002 over bore diameter and loaded around 1500 fps. You use the 300 or 400 pace setting for 100 yards.

Ivan

ETA: lever guns! Most of the Finnish rebuilds manufactured rifles have .308 bores, as do the few Winchester 1895 lever guns!

Great rifle--one of my favorite war-time movies

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John

Slug the barrel! I shoot .313 cast bullets from my two M-N's.

One or two load manuals would be a good place to begin. Start with whatever is recommended.

Personally, I wouldn't worry about a WWII Mosin.

Mosin Nagant Torture Test: Part 1 - YouTube

... they use both .311 and .312" diameter and pretty much sez what ya'll do. The barrels vary and slugging/experiment is the way to go.

Thanks!

PS I really like this. It's a great shooter and I love the open v-notch sights that enable me to see the target well rather than squinting through a peep.

PPS. Silly me. I've got some factory PPU ammo that I know shoots ok. Why don't I just measure that for starters???

PPPS It seems that most factory ammo has .312" dia bullets. That's probably a good starting plac.

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"He was kinda funny lookin'"

7.62 = .308
The correct answer is to slug your barrel and use that dimension. It's the only way to really know .

I got a MN a few years ago and to make sure what bullets I needed to use I slugged the barrel. As mentioned above, there were millions manufactured and prolly in different factories under different circumstances. Mine slugged at .312"...

The slugging is a good idea and I think I'll do it since I have no idea how much it has been shot. (It's a 1937 manufacture) And 7.62 mm does convert to .308" which does work in my American made .30 cal. rifles.

I'm not sure, except for the '3 line' specification (.30 caliber) how the Russians arrived at bullets several thousandths larger than .30 cal.
The whole series of .30 cal rifles included the .303 British, the 7.7mm Arisaka and the 7.62 Mosin, all of which are larger by a few thousandths than .308.

Anything under a 7.92mm, usually referred to as 8mm, seems to be a .30 cal.There doesn't seem to be any .31 caliber cartridges.

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"He was kinda funny lookin'"

Which rifle? The one that he used to shoot through a peephole (and take out five Germans), or the one with the scope?

I can't say why the Russians selected their bore size for the M-N (I bet someone here will share a great explanation!) but I can say that it's been suggested that their Makarov pistol was designed slightly larger than the common 9x19 (diameter, I mean!) because they didn't want any other Nation's soldiers to make use of their ammo if lost or otherwise out of Russian hands.

Or your Czarist boat anchor 😁

Jacketed bullets are very forgiving as to fit. An undersize or oversize bullet may work fine. I'd try at least two diameters, starting with .308.

With cast, use the largest diameter that will allow chambering a loaded cartridge without difficulty. This will likely provide best accuracy (providing alloy strength is compatible with pressure / velocity). Very slight engraving of the bullet nose or body, whichever happens first, is important with cast bullets in a rifle.

Slug the bore if you wish. Sometimes that's helpful; usually it's not necessary.

Watched a video for the two guys that kill weapons.........

DON"T ever load that rifle with......
15grs of Red Dot
57 grs of H335
a compressed load of 4350 or
47grs of 2400 powder !!!!

Other wise, the bolt will open without any problems.

It's a European convention of referring to land diameter rather than groove diameter.

The .303 British has a .312" or 7.92mm groove diameter but has a .303" land diameter, so it was called the ".303" rather than the ".312" or the ".3118".

The British used the same convention with the .280 Ross and the .280 British, which both have 7mm (.284") groove diameters and .280" land diameters.

The Russians did the same thing with the 7.62x54R. It has the same 7.92mm or .312" groove diameter but they also used very deep grooves with tall rifling with a resulting more diameter of .300", or 7.62mm. Thus it is the 7.62x54R, and not a 7.92x54R. The followed the same convention of naming I based on land diameter with the 7.62x39.

The Japanese followed the European naming convention with the 6.5 Arisaka round, which has a 6.7 mm groove diameter (.264") but a tall rifled .256" land diameter which is 6.5mm. Thus it was the 6.5x50mm Arisaka, not the 6.7x50mm Arisaka.

The Japanese were impressed by both the 7.92x57mm Mauser, and the .303 British. The Imperial Japanese Navy just created a knock off of the .303 British cartridge and called it the 7.7x56R, again referencing the land diameter, like he British, but stating it in rounded metric units. The Imperial Japanese Army adopted the 7.7mmx58mm Arisaka as more or less a slightly smaller caliber copy of the German Mauser round, using a .312" bullet like the Navy. Since it had a land diameter of .303" or 7.696mm, they just rounded up to 7.7mm when they named it.

You see the same in thnaming convention used in the 6.5x55 Swedish, the 6.5x54 Mannlicher-Schoenauer and the 6.5x52 Carcano cartridges. They all have a .264" (6.7mm) groove diameter, but are named based on a .256" (6.5mm) land diameter.

The European 7.65s are the also named the same way. The 7.65x53 Belgian Mauser has a .312" (7.92mm) groove diameter, but uses the 7.65mm name to denote the .300 bore diameter.

The 7.92x57mm Mauser, commonly called the 8mm Mauser in the US, has a .323" or 8.2 mm groove diameter and a .312" land diameter.

The parent cartridge for the 7.92x57 was the Patrone 88, adopted in 1888 with a land diameter of .312" and a groove diameter of .319" with .318" diameter bullets. Accuracy was poor so they changed the groove diameter to .323" to get taller rifling that would hopefully be more accurate (but strangely retained the .318" bullet). It wasn't any more accurate, but it explains some of the deeper groove/taller rifling efforts noted above in the 7.62x54R, etc.

The Germans redesigned the cartridge using the "S" type spitzer bullet. They retained the .323" groove diameter and used a land diameter of .312" or 7.92mm, and thus named it the 7.92x57 Mauser.

If you think about it, we also followed the same convention with the 6mm Lee Navy (.244" land diameter and .236" groove diameter),as well as with the .308" groove diameter cartridges like the .30-30, the .30-40 Krag, the .30-03, and the .30-06 which were all named based on their land diameter. We also call it the 270 Win, rather than the "277 Win".

It's only fairly recently that we started naming cartridges like the .270 .308 Win, .243 Win, .244 Rem, .223 Rem, etc based on their groove diameter. And you've probably noticed that we have our fair share of rounds like the .280 Rem, the 260 Rem, the 6.5 Creedmoor, etc, that are again named based on land diameter.

I need to start reloading for my 7.62x54R rifles.



Some shooters have gotten good results with .308" bullets in the PSL. I'm planning on giving them a try first.

I don't know about the peephole but I use the iron sights, no scope.

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"He was kinda funny lookin'"

..as they have had no trouble making enough guns and ammo to arm about everybody in the world.

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"He was kinda funny lookin'"

That is a great dissertation that answers the original question and about anything anybody could ask about naming conventions.

I'm going to have to digest it though, it's kinda late.

Various notes:

This is a 1937, which should be a pretty good year, a late model while they still thought they were ok with the big Hit man. It seems very well made and it shoots pretty good with PPU ammo that I got mostly for the brass to reload. Of course I've only shot it a couple of times. I love it, having shot one, I decided I had to have one.

I think named a cartridge was pretty easy until they started filling in the gaps and having guns that were practically the same caliber, but different cartridges. I kind of like the 'whatever caliber' X 'cartridge length'. But saying 9mm or .38 caliber nowadays doesn't cut it.

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"He was kinda funny lookin'"

What cruel sarcasm! Those are Joe Stalin national match rifles. My friend Frank told me so -- he owns the complete set of 23 rifles and 26 Nagant revolvers.

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S&WHF 366

That's something I like. Rugged and strong and not made to be babied or even treated decently. The action did take extreme abuse before giving out and then it was just a chamber 'bend out' with no parts flying. I like that big honking bolt and the action made out of a steel billet that you have to manhandle and slap around to open and close. Kinda like what the guy said in the video. You gotta be a real man to operate it and a woman has to be a real man, too. They did quite well with them defending the homeland. FUN!!!!!!

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"He was kinda funny lookin'"

Tie a rope in the middle and it has the weight and length to snag the bottom. Pull it up and wash it out and it's a rifle again.

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"He was kinda funny lookin'"

I like my 91-30 because it has a very nice trigger pull for a mil-surp, not heavy at all. The bad news is the chamber is ridiculously oversize - spent cases look like 7.62 improved or 7.62 beltless magnum, LOL. And a fair % of the cases split open. Because of that I never considered reloading for it. It would need a rebarrel and for the money I could just go get an entry level bolt gun in 308.

The rifle goes into retirement when I've used up the last of the cheap milsurp ammo. 1320 shots of fun out of a $99 rifle. Good deal.

303 British is close. .303 is the bore + .004 groove depth +.004 for the other groove = .311 (this is what my BSA No.4 MKI measures)
that's almost 31 cal. Wait...just what what is considered 31 cal??????
I'm confused too ! Slugged the barrel and came up with .311 +.001 = .312. The Lee mould cast bullets @ .3125...Perfect!
Or at least close enough,
Gary

Powder coat those badboys & get ta loadin'!

I've long been a member of the "couldn't give me a Mosin Nagant" club haha and while brainstorming a few years back, I came up with a fantastic idea of what to do with a truckload of them -- attach them to fence posts around your property line, have each rifle loaded with a clip of ammo and no bolt, with the action having some manner of a cover. Then, simply keep a Mosin bolt in your pocket or on the 4-wheeler, tractor or truck and you always have fast access to a rifle if you are able to get near the perimeter of your land or any fence line.

Also thought it was be fantastic to have a small canoe built from Mosin Nagant rifle stocks, or maybe a log cabin of them.

Actually, most 6.5 Carcano rifles and carbines have .267-.268" groove diameters. That is why a most .264" commercial ammo does not shoot well in them. That's how the "Carcanos are not accurate" myth was born. Here's some data.

SHOOTING THE 6

The reason I say "most Carcano rifles and carbines" is because late war production gun built under German supervision appear to have a more conventional groove depth. Late war M41 rifles produced at Armaguerra Cremona are renowned for their tight bores among Carcano reloaders.

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Release the Kraken

Back when I was shooting and loading for the .303 British, 7.62 M-N and 7.7mm Jap, I used .308 bullets in all of them, and performance was OK. Some may know that there were huge numbers of captured 7.7 Arisaka rifles simply rechambered for .30-'06 after WWII by the South Koreans. And also large numbers of post-war GI bring-backs to the US given the same treatment as part of sporterizing.

Don't sell them short. They have a rather ingenious magazine system, and will outlast most newer bolt action designs.
Not pretty or finely machined, but they are good enough in the places that count.

Maybe the Brits, Russians, Japanese etc. refer to GROOVE DIAMETER, and we Americans go by BORE DIAMETER.

The Swiss 7.5x55mm actually uses a .308 (7.62mm) bullet. In fact, the early U. S. .30 caliber military bullets were knockoffs of the Swiss bullet design. U. S. Ordnance was very impressed with the 7.5 Swiss.

One thing you may have to pay attention to is the size of the neck expander button used in your reloading dies. Case necks will have to be sized to securely hold the seated bullets, and a couple of thousandths difference can spell the difference between serviceable ammo and unserviceable.

That's true. The Lee 7.62x54R sizing die sizes the neck way down and the expander ball opens it up to only 0.305" for use with 0.308" bullets. I first bought a whack-a-mole Lee loader for 7.62x54R which neck sizes only and brings the neck down to 0.310". My 91/30 slugged at 0.312" so I beagled my mold to drop at 0.315" using copper foil tape and opened up my push through sizer to 0.314". I still use the press mounted seating die to seat the bullets.



Russian conscripts had to shoot full power spam can ammo which can be tolerable with a heavy winter coat but is brutal on your shoulder at the range in 90 degree short sleeve weather so I down load my 185g bullets to a manageable 2000 fps with Rx7 and also have some plinker loads using 10g Unique which is just fine for punching paper with open sights at 50 yards.

They are made to be rifles but they can double as baseball bats in short breaks between German attacks.

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"He was kinda funny lookin'"

Both my 91/30 & M44 have .312" groove bores and shoot .311" jacketed bullets in the 150 to 180 gr. range very well. These days I pretty much just shoot cast lead all the time as it much cheaper and I can do anything with cast lead at the ranges I shoot at that I can do with the more expensive jacketed bullets.

I use RCBS dies that come with both .308" and .311" expanders as well as a NOE case neck expander plug that basically turns my Lee Universal expander into a Lyman M die.

My favorite cast bullets are the Lee 160 gr. RN and Lee 185 gr. RN in both rifles as well as a 215 gr. FP custom mold I had cut for the 91/30 to fill the long throat that I size to .314"

I like Alliant 2400 for general purpose shooting loads but for higher velocity I like H4895 to give my bullet a slow gentle push. Below in one of my first test 5 shot test groups I shot with the new bullet, I'm not at Max load / velocity as of yet as I have around 8 grs. more to work with.


Another average group I get with the Lee 185 gr. in the 91/30 with 2400.


If anyone has old shoulders like me that can't take the beating of the steel butt plate after quiet a few rds. of surplus HB ammo this small recoil pad fits the Mosin stock perfectly and works like a charm. Some pretty good videos on reloading for the Mosin rifles can be found here.

One of those slip-on Limbsaver type pads works fine too. Even though the pad lengthens the pull, unless you are wearing a heavy wool coat while shooting, the added length actually helps.

I used Hornady .312 150 grain and 174 grain flat base bullets in both my British Enfields and Mosin Nagants. (noisy maggots)

Do not use boat tail bullets or steel core pulls, a worn muzzle will cause the boat tail bullets to tip and the steel core bullets will not expand and fill the bore.

If you want you can try the Hornady 170 grain .308 bullets made for the 30-30 Winchester. These bullets have a softer lead core and when fired and kicked in the seat of the pants will expand to bore diameter.

Your accuracy will be effected by any muzzle erosion so I would start with the .312 Hornady bullets. You will have two .312 bullets to chose from the 150 grain and the 174 round nose that has more bearing surface. Meaning the 174 grain bullet has more surface area to grab worn rifling to improve accuracy.

I agree with the tip to use the Hornady .312 jacketed.

I've got a 1930 Tula hex. I slugged the bore, and got .315 (!) groove diameter. I would recommend you slug the bore before you get too involved with it.

I'm currently using the Hornady .312 jacketed, and getting good results with it. I'm shooting 3.5" groups at 75 yds with irons, and am getting much better as I practice.
The bore of my MN , while dark and lightly pitted, has strong rifling. I've retrieved a few of the fired bullets, and they show good rifling on the jackets, indicating a good 'grip' in the bore. I haven't felt the need to go heavier with jacketed.

My longer-term goal is shooting at the local club military matches. I recently received a mold, NOE calls it a 316213 RN. This is NOE's version of the Lyman 312299, but bigger around, for the monster bore size of some Mosins
Mine casts at .3165-.317, with a .305 nose, using CWW with 1% added tin. A very nice mold, which casts wonderfully. I'm wanting to shoot these at ~1700 - 1800fps, and I'm just waiting in a custom H&I die to get on with it.