Mannlicher Schoenauer 1954 bolt safety stopped working

[Nevada Smith]

I'm asking for help, please:

When I attempted to disassemble a working bolt on my new-to-me 1954 MS according to the manual, and by watching a 60 second video on YouTube titled "Steyr Mannlicher-Schoenauer MC bolt dissasembly" (sic), two things happened:

1) the nut for the firing pin (#47 on page 16 of the manual) could not be removed despite soaking this end of the bolt in Kroil for a couple of hours

2) while trying to remove the nut, at one point the head of bolt (#41 on page 16 of the manual) came off; I believe I may have incorrectly orientated it when I put it back on, perhaps causing the bolt safety to lock up?

Right now the bolt safety is stuck in the fire position. The tang safety works as it should.

When the bolt is cocked and locked, the safety catch (#39) is fully pushed out of the cocking block (#38) toward the shooter, and it can be rotated about 5 or 10 degrees before coming to a hard stop, nowhere near the 180 degrees needed for Safe position.

 

[Nevada Smith]

More info:

• If the bolt is removed from the rifle and manually de-cocked, the bolt safety works as it should.
• All serial numbers match.

I believe if the bolt could be disassembled, cleaned, and reassembled, all would be well.

However, the sticking point (no pun intended) is: how to remove the stuck knurled nut for the firing pin without damaging it (or its finish)?

(I've already tried Kroil. Maybe I should apply some heat to that area with a heat gun?)

 

[SaintPanzer]

Do you have a link to the manual/diagram you are using? I'm not sure I'm picturing the correct "nut for the firing pin".

 

[Nevada Smith]

Do you have a link to the manual/diagram you are using? I'm not sure I'm picturing the correct "nut for the firing pin".

Here's the link to the manual for the Mannlicher-Schoenauer Sporting Carbine Model 1950:

https://www.steyr-arms.com/wp-content/uploads/2021/04/Owners-manual-Mannlicher-Schoenauer-Modell-1950-english-1.pdf

Page 16 ("Bolt and Firing Pin") is below. Part #47 ("Nut for firing pin") is what can't be removed from my rifle's bolt.

 

[SaintPanzer]

OK, just wanted to be sure. My M1910 has a Lyman diopter on it, so there is a small screw that needs to be backed out first, but you shouldn't have that problem. You should NOT need Kroil, etc. First, make sure the bolt is not cocked. Then, place the bolt face down on the bench, so you are looking directly at the bolt. Push down on the flag safety, and as that is pushed down, you should be able to turn the nut 90 degrees. You will NOT be able to do this if the bolt is cocked (you need all tension off the spring). See Step 4 on the attached.

 

[Nevada Smith]

​

SaintPanzer: Thank you for your reply.

I realize the bolt was designed to be stripped without tools, and by design the nut should come off with finger pressure & hand torque.

However the nut on this bolt won't budge.

 

[SaintPanzer]

Does the flag safety move when you push down on it? There's a cam that prevents the nut from twisting. If the safety does not move against its spring, work on getting motion there (it may be gunked up) first...

 

[Nevada Smith]

Does the flag safety move when you push down on it? There's a cam that prevents the nut from twisting. If the safety does not move against its spring, work on getting motion there (it may be gunked up) first...

Yes, that part works as expected.

I even tried pushing the flag safety with my body against a bench to make certain the safety flag spring was fully depressed whilst trying to twist the bolt nut.

Right now the bolt / nut is soaking in Kroil in hopes it will counteract whatever is keeping the nut from moving.

 

[Nevada Smith]

Here's the link to the "Steyr Mannlicher-Schoenauer MC bolt disassembly" video referred to in my original post. (I can't embed it here because the owner of the video has disabled playback on other websites.)

 

[SaintPanzer]

I will try and find the time to play with mine this weekend, and see if there's something obvious we are missing. IIRC, there would have to be a lot of gunk in there to stop it from twisting.

 

[Nevada Smith]

I will try and find the time to play with mine this weekend, and see if there's something obvious we are missing. IIRC, there would have to be a lot of gunk in there to stop it from twisting.

Thank you, sir!

 

[SaintPanzer]

I played with mine a little bit today... Learned a bit that I had forgotten.
The flag safety does have a small cam on it, and that holds a cut out piece on the nut. If there is anything keeping the flag from completely seating when you push on it, it may stop the nut from turning. Your comment that the bolt head may have been incorrect makes me wonder what that is affecting. the "flat" part of the firing pin does sit in a groove, I wonder if that might be canted or otherwise impinging on the nut? The rear of the pin is threaded, could it be galled? Without it in my hand, it's difficult to tell what else might be tried, it may be time to take it to a smith.

 

[Nevada Smith]

Thank you, SaintPanzer, for taking time out for this.

You may be on to something vis-a-vis the "flat" part of the firing pin.

If I find out anything, or a smith does, I'll post it here.

Meanwhile, wishing you a Happy Thanksgiving!