"Sticky" Mosin bolts...

[cyclone]

.

The "best" explanation I've heard for the stickiness of Mosin Nagant rifle bolts is that, like the Nagant revolvers, the Russian "refurbishment" process made things a lot gummier than when the firearms first left the production line...


(1) Any agreement/dissent/details as to this theory?

(2) Did the refurbishment process involve additional heat-treatment(s)?

(3) Is/was the "demon cosmoline" and/or the sinful shellac (at least in-part) to blame, some way, some how?



Anyhow, thanks in advance...

 

[enefgee]

I always thought that it was a combination of poor materials and bad workmanship. That isn't the knock that it might seem to be, lots of Mosins were built while half of the country was occupied by some very nasty people, and the other half was being run by some very nasty people - amazing anything got built at all.

 

[7ECA]

That isn't the knock that it might seem to be, lots of Mosins were built while half of the country was occupied by some very nasty people, and the other half was being run by some very nasty people - amazing anything got built at all.

That's a rather gross exaggeration - the proportion of occupation that is.

Just a rough look at the numbers. The extent of the Wehrmacht advance to Moscow saw them get within 5 miles of the city. For measurement purposes, say from the centre of Moscow to the furthest reaches of Eastern Russia is around 4,000 miles. Moscow to the Western Russian border with Belorussia/Belarus is between 250/260 miles - if we want to be a bit more Soviet-minded, going to say Brest, Belarus would be a bit over 600 miles, or further West to the Western extreme of Ukraine is around 830 miles.

If you want to call it a 5000 mile wide empire, temporarily occupying say 1,000 miles is a fair bit less than half. The reason Moscow was held by the Soviets, was the ability to call up troops from Siberia.

 

[gewehr76]

I always thought that it was a combination of poor materials and bad workmanship.

This is incorrect assumption. Before each part make on to assembly line it had to pass quality control and stamped with factory logo, star for Tula and Triangle with arrow for Izhevsk. Parts that were replaced in the field or spares had to be filed to fit each rifle individually and may not have inspection stamps left, but they all have technological stamps of various shapes and sizes. Which indicates that they were made to specks. Poor materials and bad workmanship would not pass quality control.

 

[enefgee]

This is incorrect assumption. Before each part make on to assembly line it had to pass quality control and stamped with factory logo, star for Tula and Triangle with arrow for Izhevsk. Parts that were replaced in the field or spares had to be filed to fit each rifle individually and may not have inspection stamps left, but they all have technological stamps of various shapes and sizes. Which indicates that they were made to specks. Poor materials and bad workmanship would not pass quality control.

So it was a bad design? I've never had an Enfield that needed you to "tap" the bolt handle with a tool to get it open, or a Mauser for that matter.

 

[bearhunter]

This is incorrect assumption. Before each part make on to assembly line it had to pass quality control and stamped with factory logo, star for Tula and Triangle with arrow for Izhevsk. Parts that were replaced in the field or spares had to be filed to fit each rifle individually and may not have inspection stamps left, but they all have technological stamps of various shapes and sizes. Which indicates that they were made to specks. Poor materials and bad workmanship would not pass quality control.

You're right to a point. I have a couple of M91 rifles from pre 1900 and a US made Remington from 1917 with Czarist and Finn SA stamps. The two Russian built M91 rifles are super slick, when properly lubricated. The US rifle has a double stamped bolt, floorplate but retains its original walnut stock, without finger grooves. It's slick as well, as long as it's properly lubed.

IMHO, the materials used for those early rifles was the best available for the purpose at the time of production. All three shoot better than the M91/30 rifles I have.

There are several different M91/30 rifles in the safe. Most of them have original matching numbers. There were plenty to pick from back in the day and I had the opportunity to sort through thousands to find the jewels. The early hex receiver rifles are much slicker to operate than the later round receiver models. Tolerances are tighter on the early models, including the mixmasters. The later rifles are sloppier and I can tell you that I have done Brinnell hardness tests on some of them. The later, war time production rifles are slightly softer than pre war and especially pre revolution rifles at the front receiver ring on the underside.

These rifles are notably less slick, even with matching numbers, than their predecessors.

The same thing occurs with US Springfield receivers. The early rifles with the different heat treating are or can be made to be butter smooth. The later rifles can also be made slick by judicious stoning and polishing but the later O3A3 models can come close but no matter how much effort is put into them, can't quite achieve the slickness of the 03s.

The steel used in all of them is FINE for the purpose it was intended to perform. Strength is way in excess of what is required by their ammunition.

I have only tried to slick up one Mosin action. An M44 that bubba had his way with and the bore was rotted from using corrosive ammo without cleaning. Luckily I had a spare M91/30 barrel that came from a rifle turned in for destruction to the local police department over 15 years ago. They cut the receiver in half, through the magazine/stock/bolt and threw it in a scrap bin.

I spent a lot of time on that factory 11 receiver to make it smoother than it was. Don't get me wrong, it was better than average already. I just wanted it to be slicker and it was the dead of winter, sooooooo.

IMHO, after several hours of hand stoning all of the contact surfaces to a mirror polish, I achieved nada. It was slick as long as there was good lube in the race ways. Thankfully it shot well.

I worked on this rifle because I wanted to see how much velocity I could squeeze out of it, with a cut down/recrowned, 22 inch bbl. The receiver had been drilled and tapped for a scope and with some work I managed to get the bolt handle welded on at an angle very similar to most sporting rifles, so I could mount the scope lower to the axis of the bore. It was actually a pretty decent hunting rifle. More than smooth enough for the purpose and a consistent moa shooter with 174 grain .311 diameter CIL soft point bullets I had on hand.

I don't believe the steel used in the original M91 rifles is the same as that used in the later M91/30 rifles. The receivers of course and maybe the bolts as well.

At the very least the steel went through different heat treating processes. Then of course where the receivers/bolts were made has to be factored in. Russia/France/Belgium/US and later Poland/China. Maybe even a few more countries. To my knowledge, the Finns never made Mosins. They just bought/captured and refurbished existing rifles.

I have never had to "tap the bolt" to get it open on any Mosin. Your rifle may have an issue with headspace. I have had Lee Enfield rifles with tight headspace require extra effort to open them, even if the cartridge wasn't fired. That's the nature of the beast with rimmed cases and varying rim thicknesses. No 1 rifles can be tight to the point they won't close on some rims.

The Mosin design is over complicated but it's very strong and not a poor design.

 

[gewehr76]

So it was a bad design? I've never had an Enfield that needed you to "tap" the bolt handle with a tool to get it open, or a Mauser for that matter.

Apples and oranges, when comparing to other designs. How can it be bad design when millions of rifles were produced.

You're right to a point. I have a couple of M91 rifles from pre 1900 and a US made Remington from 1917 with Czarist and Finn SA stamps. The two Russian built M91 rifles are super slick, when properly lubricated. The US rifle has a double stamped bolt, floorplate but retains its original walnut stock, without finger grooves. It's slick as well, as long as it's properly lubed.

IMHO, the materials used for those early rifles was the best available for the purpose at the time of production. All three shoot better than the M91/30 rifles I have.

There are several different M91/30 rifles in the safe. Most of them have original matching numbers. There were plenty to pick from back in the day and I had the opportunity to sort through thousands to find the jewels. The early hex receiver rifles are much slicker to operate than the later round receiver models. Tolerances are tighter on the early models, including the mixmasters. The later rifles are sloppier and I can tell you that I have done Brinnell hardness tests on some of them. The later, war time production rifles are slightly softer than pre war and especially pre revolution rifles at the front receiver ring on the underside.

These rifles are notably less slick, even with matching numbers, than their predecessors.

The same thing occurs with US Springfield receivers. The early rifles with the different heat treating are or can be made to be butter smooth. The later rifles can also be made slick by judicious stoning and polishing but the later O3A3 models can come close but no matter how much effort is put into them, can't quite achieve the slickness of the 03s.

The steel used in all of them is FINE for the purpose it was intended to perform. Strength is way in excess of what is required by their ammunition.

I have only tried to slick up one Mosin action. An M44 that bubba had his way with and the bore was rotted from using corrosive ammo without cleaning. Luckily I had a spare M91/30 barrel that came from a rifle turned in for destruction to the local police department over 15 years ago. They cut the receiver in half, through the magazine/stock/bolt and threw it in a scrap bin.

I spent a lot of time on that factory 11 receiver to make it smoother than it was. Don't get me wrong, it was better than average already. I just wanted it to be slicker and it was the dead of winter, sooooooo.

IMHO, after several hours of hand stoning all of the contact surfaces to a mirror polish, I achieved nada. It was slick as long as there was good lube in the race ways. Thankfully it shot well.

I worked on this rifle because I wanted to see how much velocity I could squeeze out of it, with a cut down/recrowned, 22 inch bbl. The receiver had been drilled and tapped for a scope and with some work I managed to get the bolt handle welded on at an angle very similar to most sporting rifles, so I could mount the scope lower to the axis of the bore. It was actually a pretty decent hunting rifle. More than smooth enough for the purpose and a consistent moa shooter with 174 grain .311 diameter CIL soft point bullets I had on hand.

I don't believe the steel used in the original M91 rifles is the same as that used in the later M91/30 rifles. The receivers of course and maybe the bolts as well.

At the very least the steel went through different heat treating processes. Then of course where the receivers/bolts were made has to be factored in. Russia/France/Belgium/US and later Poland/China. Maybe even a few more countries. To my knowledge, the Finns never made Mosins. They just bought/captured and refurbished existing rifles.

I have never had to "tap the bolt" to get it open on any Mosin. Your rifle may have an issue with headspace. I have had Lee Enfield rifles with tight headspace require extra effort to open them, even if the cartridge wasn't fired. That's the nature of the beast with rimmed cases and varying rim thicknesses. No 1 rifles can be tight to the point they won't close on some rims.

The Mosin design is over complicated but it's very strong and not a poor design.

Interesting observations. There bound to be some differences between manufacturers. No way to make them all the same across the board.

 

[diegocn]

If bolt is sticky only after firing, it means the case is hard to extract. From my experience it's either:

1. Chamber needs to be cleaned, not cosmoline, but dirty chamber, possibly from rust. An example is my friend's 91/30. We used to bring a mallet with us every range trip due to hard to lift bolt handle. I later found out he "cleans" the rifle by throwing it into the bathtub after shooting corrosive (if he have time lol). He eventually sold that 91/30 to me for pretty much free. I spent an hour to cleaned it, consumed 3 9mm (oversized) brass brush in the process, lubed it up. Bolt never stick any more since then.

2. Loose headspace combined with weak Chinese surplus ammo. Chinese surplus 54R (only type commonly availabe these days) is weaker at the base than Russian/eastern bloc surplus, or Barnaul ammo. This combined with loose headspace caused the case to expand at the base near the head, causing difficult to extract (thus hard to turn the bolt handle).
Example is not mosin my SVT40. It would have every single Chinese surplus stuck in the chamber, rim torn off by extractor. I measured the headspace it's within field gauge tolerance. Switch to Bulgarian surplus and Barnaul, the rifle shots flawlessly. The hard to extract is less pronounced in mosin due to the stronger initial extraction, but none the less this could cause the hard to lift bolt handle after firing.

I have more than a handful of 91/30s, all round receiver made between 1938 to 1944. None of which have sticky bolt (anymore). All of them shoots within 4moa. Best one is a Ukrainian pu reprod shooting slightly less than 2 moa with hand load. I took that rifle out to 600m have have some success on a 12"x12" plate once I overcome the ergonomic shortcomings of the 1940 optic technology. Another gent with an authentic PU mosin on 600m shoot day got to 500m with surplus ammo.