Mosin Nagant bolt groups interchangable?

[Clark]

Measure a bunch of Mosin Nagant bolt heads.
The seem to be interchangeable... 91/30, M59, or M44, it does not matter.
All within 0.001"


What is NOT interchangeable is barrels and receivers.
The thread clocking is custom.
And it is not just getting the sights to point straight up.
The real problem is extractor relief cuts. For the rim to headspace on the barrel, a tiny more than 180 degrees of no extractor relief cut needs to be there. The 90 degrees of bolt rotation PLUS the width of the extractor all work together to make is a tight fit.

 

[Orion8472]

Thanks Clark for your input here. Good experiment!

I probably really didn't NEED to switch bolt faces, but did so just to be "safer".

To everyone else, . . . I didn't find any import marks. SO glad I got the other M44 in order to make one very nice one.

 

[303tom]

I would like to stick my .02 into this fray, while head space is a concern in all firearms, it is not as much of a concern with rimmed cartridges, hence the revolver. With that said, you should ALWAYS check or have checked the head space of said rifle.............

 

[Orion8472]

After discussing this topic with a gunsmith, I am going to take both M44s to a gunsmith to check the headspacing, . . . just to be safe. It is a powerful round, afterall.

 

[bainter1212]

DEFINITELY cheaper to buy the No-Go gauge yourself. A hammer and punch removes the extractor in a few seconds (it's dirty under there, believe me). Insert gauge and try to close bolt. Super simple. Should be about 30 options through Brownells.

 

[Ar180shooter]

D'uh.

Assuming that they were each properly headspaced to start with, take the bolt head or face from the rifle you intend to be the one you use, and the bolt body from the other rifle, if this is what you choose, and assemble them.

The headspace is determined by that little bolt head with the extractor claw in it, not the bolt body or the striker. If you use the same bolt head (the part with the extractor) from the rifle it was properly headspaced from, you should be good to go.

HTH.

I was thinking the exact same thing.

 

[Orion8472]

As an update, I took both M-44s out to the range, yesterday, and fired two rounds each [using a metal clothes hanger to pull the trigger]. They both operated normal and the casings showed no abnormalities in casing or primers. I can take some shots of the spent casings if you all want to see them.

On a side note, . . . it doesn't take but one round to draw a crowd.