mauser bolt hardness on open

[CCAMERA50]

hallo ,

i bought recently a nice Persian Mauser 98/29

during tests at the range i noticed that after each fire the bolt
was considerably "hard" to open ( by a hand but with a good effort )

.....only on open ......and without traces of overpressure ( the load
was about 44 gr of Vhita N140 under a Sierra MK HPBT 200 gr )

well, i do not know , the possible reason of it - i know this bolt load
the spring of the firing pin on open and the spring it is hard

....may be the shoulders of the receiver worn ? so on open the bolt
could have to pull forward the case

please some "Mauser spcialist" can help me ?

thank you in advance for some opinion

CC

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[CCAMERA50]

.....not "pull" , but "push" forward

sorry

[Patrick Chadwick]

( the load was about 44 gr of Vhita N140 under a Sierra MK HPBT 200 gr )

That is well within the range (42.7 - 47.5 of N140) published in the Vihtavuori reloading manual for the 8x57IS with a 200gn bullet. So one would not expect any overpressure or signs thereof.

Take a very close look at the case when it is extracted. Can you see any bright marks or bumps? There may be damage to the chamber in the form of rings or rust pits. When a cartridge is fired, the case expands to fill all these recesses, and if the rings or pits are deeper than about 0.002" the case will be hard to extract.

WARNING !!! If your chamber has such a defect, do NOT try to make a chamber cast - it will be impossible to extract!

[CCAMERA50]

That is well within the range (42.7 - 47.5 of N140) published in the Vihtavuori reloading manual for the 8x57IS with a 200gn bullet. So one would not expect any overpressure or signs thereof.

Take a very close look at the case when it is extracted. Can you see any bright marks or bumps? There may be damage to the chamber in the form of rings or rust pits. When a cartridge is fired, the case expands to fill all these recesses, and if the rings or pits are deeper than about 0.002" the case will be hard to extract.

WARNING !!! If your chamber has such a defect, do NOT try to make a chamber cast - it will be impossible to extract!

Thank you Patrick ,

Usually , the first time i shoot a new gun , i make a close case inspection ( it the first step of a
personal standard procedure at the range - ....after inspection and cleaning and slugging at home)
well.....i saw nothing remarkable -

i inspected the bolt lugs but ....nothing remakable
i also ( after it ) stripped the whole bolt and tested it for some kind of tolerance wehn closed
( without spring , firing pin , and all the parts on the rear ) - nothing doing

....i do not know waht to think again ....a inspection of the lug recessees by a borescope ?

[WarPig1976]

I have a Mosin Nagant that I had to shim the rear action screw because without it when tightened I guess the receiver flexed just enough to bind the lugs. Just cycling the bolt I could feel slight resistance but after firing I had to beat it open. All good now....

[CCAMERA50]

@ WarPig1976 ................................
me also - on my K31 scissors and Coke aluminium tin work better than ...the better GP11 crtg
unfortunately in this case it do not help - i tested immediately your theory ......nothing
.................................................. ....

i think remain me only to try to test ( like just told me a friend ) the gun with another bolt from another similar Mauser
...if the problem there is still / or not , that could indicate where "go to looking"
the shoulders or the bolt : - || correct ?

a opinion ?

[CCAMERA50]

.....none ??

[Al Diehl]

I have a Mosin Nagant that I had to shim the rear action screw because without it when tightened I guess the receiver flexed just enough to bind the lugs. Just cycling the bolt I could feel slight resistance but after firing I had to beat it open. All good now....

This describes a Finn Model 91 I have pefectly. How much shim did you have to use to correct this?

Normal cycling no problem but, fire it and you have to use a mallet to open it.

I have cleaned the chamber and even made a crocus cloth polisher and ploished the chamber. No luck. I will try the shim up.

Thanks.

Al

[WarPig1976]

Two easy checks come to mind. I'm sure you have already, but make sure there's no cosmoline or otherwise gunk hiding in the receiver and #2 make sure you have the proper spring in the bolt. That exhausts my layman trouble shooting skills.

[CCAMERA50]

Two easy checks come to mind. I'm sure you have already, but make sure there's no cosmoline or otherwise gunk hiding in the receiver and #2 make sure you have the proper spring in the bolt. That exhausts my layman trouble shooting skills.

Hi ,

first , thank you for opinion

...all the cosmoline elimination it is the first operation i make when a gun come into my hom
...the firing pin spring , it seem to be jus his own , ( ...effectively too "hard" ) however to
"improve" the trigger ...shoot ( correct word ? ) i made a softer spring to test tomorrow
when i will go again to the range for test again

....even renting the K98K range property to see differences also trying a bolt exchange

....continue to the next episode

CC