Mosin bolt interchangeability

CoverFire

CoverFire

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I have a guy selling me a bolt for 80 bucks with a bent handle for a pu setup

My bolt guide is bent so my bolt assembly is decommissioned atm

I cant check head spacing until I get the bolt in person but by then it's to late and I'll already paid for it.

Are there any concerns I should have about swapping bolt assembly. And swapping heads?
 
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Ive swapped bolt bodies, never bolt heads.

I noticed that the bolt head does move back and forth a bit. That it might self head space. So maybe..
 
Found this on 762.54R.net

From what I also found searching. They say to headspace it. Im sure you could use your old bolt head. Further research will be needed.

1 thru 7. Bolt parts

All parts are interchangeable among all models, eras, and manufacturers with the exception of the modified "winged" M27 connector bar which requires a notched receiver. A notched receiver does not require the winged connector and a standard connector may be used in its place.
Click to expand...
 
CoverFire said:
I have a guy selling me a bolt for 80 bucks with a bent handle for a pu setup

My bolt guide is bent so my bolt assembly is decommissioned atm

I cant check head spacing until I get the bolt in person but by then it's to late and I'll already paid for it.

Are there any concerns I should have about swapping bolt assembly. And swapping heads?
Click to expand...

Mosins headspace on the bolt head ONLY. Swap the rest with impunity.
 
So what happens let's say if the head gets damaged . How does the owner replace the bolt head and create the appropriate headspace to now shoot safely?
Is this something a gun smith does, can they alter a new or used head to accomadate my barrel /gun ?
It sounds like people are saying you can't use another head not from your gun so the entire barrel is useless without the matching head ?

It kinda sucks having a whole new bolt assembly and having to switch the head over each time. I managed to find a bolt guide which is interchangeable and will replace my bent one shortly but once this new bent handle unit comes in I'd rather keep it as a whole piece and not swap heads. How do I fix this so itll work safely 100% everytime? Gunsmith ?
 
The headspace might be fine with the different bolt head, it might not be. It’s a matter of checking with a headspace gauge. Usually most bolts are pretty close. What they do in service is just keep swapping bolt heads until it passes on the headspace gauge. As it is a rimmed cartridge the tolerances on the headspace are a bit looser than a rimless cartridge. Odds are it’s fine, but no one will guarantee anything unless they have done the verification themselves.
 
I've yet to see a mosin not accept another mosin's bolt, and I've had numerous specimens. Always have common sense, if something seems outta whack, have a good look to see whats happening. They are rugged rifles, reliable, and one hell of a moose slayer. Good luck.
 
After a lengthy thread on the gunboards Mosin forum I measured quite a number of Mosin bolt-heads from my collection and was quite surprised to see the uniformity. With the exception of one very heavily worn head they all were +/- 0.001" and I have no doubt I could interchange any of them with no problem. Suggests the original machining of the shoulders in the receiver, etc must have been done to pretty exacting standards (or variance was ignored). I have read that there were bolt-heads of larger size available for armourers to adjust headspace (just like there were longer bolts for SVT 40s) and it surprises me that nothing in my collection appears to have one. Perhaps they would show up more frequently in post-war refurbs that were adjusted back to original specs?

milsurpo
 
since they don't have a way to allow gas to escape they are a poor and outdated design....the steel cases lessen case ruptures but using and full length resizing brass cases several times can lead to case rupture and extreme nastiness could ensue....checking headspace is never a bad idea...
 
so i got the bolt in and it cycled real and dummy rounds without issue, it wasnt that "much effort" to rack it but its not "hot knife through butter" smooth either.
is the only real way to check the headspacing to get one of those $40usd machined spacing gauge that is set to like 0.075" and if it cycles or doesn't cycle that way i know? or is using dummy and real rounds just as good a test aslong as it cycles properly and ejects?
 
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