Sticky bolts?

Thrawn · 06-21-2005, 11:33 PM

Okay I keep seeing posts about sticky bolts, I have two that have never gave me a problem. I did have a dragoon at one time that had a sticky bolt, but cleaning the chamber real good solved this. The other two shot fine when I got them. I have fired laquer and poly coated steel cases through them with no hiccups.

Thrawn · 06-22-2005, 12:24 AM

One of most frequent postings on all of the Mosin Nagant related forums is that of the problem of sticking bolts. Many people believe that this is related to the type of ammo they are using, others believe it is a headspace problems and still others attribute it to a rough chamber. They are all correct in their own way but often the problem is as simple as a dirty chamber!

When these rifles were placed in storage, they packed with a layer of waxy grease like preservative to protect the metal parts. Over the years some of this preservative hardened and formed a varnish like shell on the metal that is nearly transparent and very tough to break up with normal cleaning solvents. After cleaning a rifle using standard cleaning techniques, it is easy to believe that you got all of the preservative out of the chamber and off your metal parts. However, that film is still there. It's tightly bonded to the metal as a result of pitting or burrs in the chamber and it is trapped in the recesses of the locking ring where standard cleaning techniques can't reach it.

When you take your rifle out to the range and fire your first few shots, suddenly you can't open the bolt without really pounding on it. Why does this happen? When a round is fired, it generates a tremendous amount of heat and pressure in the chamber area. The charge causes the shell casing to become hot and to expand. At the same time the chamber walls become hot. The varnish like dried preservative heats up and becomes sticky. As the shell casing contacts the chamber wall and the sticky goo attached to it, there is a bonding that takes place as the metal of both surfaces cools in the first few seconds after firing. In turn, the bolt lugs are also trapped in this goo and the bolt becomes hard to open.

A rough chamber will make the problem worse by giving the goo more places to be trapped in and to adhere itself.

An out of spec chamber that is beginning to have headspace problems will also contribute to the problem by giving the shell casing more room to expand and more surface to come in contact with.

So...what do you do?

First of all, have your headspace checked to ensure you are within safe operating limits. You might consider swapping out the bolt head to see what effect this has on the headspace measurement. One you are satisfied that your headspace is safe, it is time to turn your attention to the chamber.

Use a chamber brush to clean your chamber. A chamber brush is designed to reach all of the areas within a chamber that a bore brush can not reach.

Use a good solvent like Gunscrubber or BreakFree and the chamber brush to vigorously clean the chamber. Follow that up with some Sweet's 7.62 on your chamber brush.

Take the chamber brush and Sweet's 7.62 to the range with you and fire as many rounds as possible before your bolt starts to lock up. Immediately clean your chamber while it is still hot and fire some rounds and clean again while it is still hot. Do this several times and you will notice that your bolt does not want to stick anymore.

If after this you are still experiencing sticking problems, take your rifle to a gunsmith and have the gunsmith polish the chamber and the problem should go away completely.

toolman · 06-22-2005, 01:32 AM

I am probably going to open up a can of worms here, but I suggest that the biggest problem with the dreaded "stuck bolt" problem, is none of the above. After extensive shooting with all three of mine, including a well-used 1942 91\30, near-new 1944 M-44, and a pristine 1944 M-39, I feel that the problem lies more in the bolt than the gun. I've fired hundreds of rounds each of Wolf bi-metal, Barnaul steel-cased, Russian surplus, S&B, HotShot, and handloads in Grafs brass cases. I am seeing consistant sticking in the 91\30 which has the loosest bolt and a near-mirror polished chamber. My best guess is that the bolt is binding under recoil and jamming it into the receiver walls. I can't duplicate it often enough to say this is it 100%, but it is another option to look at.

toolman · 06-22-2005, 01:44 AM

I forgot to mention,, swapping the bolt between my 91\30 and M-44 eliminates all bolt probs. with the 91\30. I haven't tested the M-44 w\the 91\30 bolt yet. The 91\30 is a sporter project and the bolt is going to be severely modified.

troy2000 · 06-22-2005, 07:54 AM

Polishing the chamber took care of the problem for me. The only ammo I'd been having serious problems with was the lacquered Czech stuff, but the rest was a little stiff. After the polishing, brass and coperwashed shells eject like they aren't even there, and the lacquered stuff comes out fine as long as I work the bolt smartly (put a little speed on it). I have a 1943 91/30.

Big Dog · 06-22-2005, 10:13 AM

If you are lucky, swapping the bolt can also result in a better trigger pull. My Finn M39 has a less sticky bolt and better trigger if I use the old M91 bolt.
Different bolts show differences in finish too. A pre-WWII Mosin often has a nicely polished bolt, while the M44 carbine is much rougher, showing lots of grinding marks. You can feel the difference in the way the bolt glides in the receiver.

View Poll Results: Whats your bolt doing?
No sticky bolt and have never polised the chamber	6	54.55%
No sticky bolt and have polished the chamber	2	18.18%
Sticky bolt and have never polished the chamber	2	18.18%
sticky bolt and did polish the chamber	0	0%
what's a bolt?	0	0%
What's a moisin?	1	9.09%
Voters: 11. You may not vote on this poll

06-21-2005, 11:33 PM	#1
Thrawn Senior Member Join Date: Aug 2004 Location: Okeefenokee Posts: 1,618 Images: 6	Sticky bolts? Okay I keep seeing posts about sticky bolts, I have two that have never gave me a problem. I did have a dragoon at one time that had a sticky bolt, but cleaning the chamber real good solved this. The other two shot fine when I got them. I have fired laquer and poly coated steel cases through them with no hiccups.

06-22-2005, 01:32 AM	#3
toolman Mr. Fixit Join Date: Apr 2002 Location: abilene,tx Posts: 5,569 Blog Entries: 22	I am probably going to open up a can of worms here, but I suggest that the biggest problem with the dreaded "stuck bolt" problem, is none of the above. After extensive shooting with all three of mine, including a well-used 1942 91\30, near-new 1944 M-44, and a pristine 1944 M-39, I feel that the problem lies more in the bolt than the gun. I've fired hundreds of rounds each of Wolf bi-metal, Barnaul steel-cased, Russian surplus, S&B, HotShot, and handloads in Grafs brass cases. I am seeing consistant sticking in the 91\30 which has the loosest bolt and a near-mirror polished chamber. My best guess is that the bolt is binding under recoil and jamming it into the receiver walls. I can't duplicate it often enough to say this is it 100%, but it is another option to look at. __________________ Don't be messin' with my gun!

06-22-2005, 01:44 AM	#4
toolman Mr. Fixit Join Date: Apr 2002 Location: abilene,tx Posts: 5,569 Blog Entries: 22	I forgot to mention,, swapping the bolt between my 91\30 and M-44 eliminates all bolt probs. with the 91\30. I haven't tested the M-44 w\the 91\30 bolt yet. The 91\30 is a sporter project and the bolt is going to be severely modified. __________________ Don't be messin' with my gun!

06-22-2005, 10:13 AM	#6
Big Dog Moderator Join Date: Mar 2002 Location: Tallahassee, Florida Posts: 10,208	If you are lucky, swapping the bolt can also result in a better trigger pull. My Finn M39 has a less sticky bolt and better trigger if I use the old M91 bolt. Different bolts show differences in finish too. A pre-WWII Mosin often has a nicely polished bolt, while the M44 carbine is much rougher, showing lots of grinding marks. You can feel the difference in the way the bolt glides in the receiver. __________________ Moderator of: AR15/M16, M14/M1A, New/Beginning Shooters and Militaria/Collectables.

06-22-2005, 12:24 AM	#2
Thrawn Senior Member Join Date: Aug 2004 Location: Okeefenokee Posts: 1,618 Images: 6	One of most frequent postings on all of the Mosin Nagant related forums is that of the problem of sticking bolts. Many people believe that this is related to the type of ammo they are using, others believe it is a headspace problems and still others attribute it to a rough chamber. They are all correct in their own way but often the problem is as simple as a dirty chamber! When these rifles were placed in storage, they packed with a layer of waxy grease like preservative to protect the metal parts. Over the years some of this preservative hardened and formed a varnish like shell on the metal that is nearly transparent and very tough to break up with normal cleaning solvents. After cleaning a rifle using standard cleaning techniques, it is easy to believe that you got all of the preservative out of the chamber and off your metal parts. However, that film is still there. It's tightly bonded to the metal as a result of pitting or burrs in the chamber and it is trapped in the recesses of the locking ring where standard cleaning techniques can't reach it. When you take your rifle out to the range and fire your first few shots, suddenly you can't open the bolt without really pounding on it. Why does this happen? When a round is fired, it generates a tremendous amount of heat and pressure in the chamber area. The charge causes the shell casing to become hot and to expand. At the same time the chamber walls become hot. The varnish like dried preservative heats up and becomes sticky. As the shell casing contacts the chamber wall and the sticky goo attached to it, there is a bonding that takes place as the metal of both surfaces cools in the first few seconds after firing. In turn, the bolt lugs are also trapped in this goo and the bolt becomes hard to open. A rough chamber will make the problem worse by giving the goo more places to be trapped in and to adhere itself. An out of spec chamber that is beginning to have headspace problems will also contribute to the problem by giving the shell casing more room to expand and more surface to come in contact with. So...what do you do? First of all, have your headspace checked to ensure you are within safe operating limits. You might consider swapping out the bolt head to see what effect this has on the headspace measurement. One you are satisfied that your headspace is safe, it is time to turn your attention to the chamber. Use a chamber brush to clean your chamber. A chamber brush is designed to reach all of the areas within a chamber that a bore brush can not reach. Use a good solvent like Gunscrubber or BreakFree and the chamber brush to vigorously clean the chamber. Follow that up with some Sweet's 7.62 on your chamber brush. Take the chamber brush and Sweet's 7.62 to the range with you and fire as many rounds as possible before your bolt starts to lock up. Immediately clean your chamber while it is still hot and fire some rounds and clean again while it is still hot. Do this several times and you will notice that your bolt does not want to stick anymore. If after this you are still experiencing sticking problems, take your rifle to a gunsmith and have the gunsmith polish the chamber and the problem should go away completely.

06-22-2005, 07:54 AM	#5
troy2000 Resident Armed Liberal Join Date: Dec 2004 Location: Southern California Posts: 9,412 Images: 9	Polishing the chamber took care of the problem for me. The only ammo I'd been having serious problems with was the lacquered Czech stuff, but the rest was a little stiff. After the polishing, brass and coperwashed shells eject like they aren't even there, and the lacquered stuff comes out fine as long as I work the bolt smartly (put a little speed on it). I have a 1943 91/30.