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View Full Version : Mauser Cocking Piece/Bolt Cam Notch Relationship


DeBee
June 25, 2000, 10:19 PM
Can anyone instuct me as to the proper relationship of the Mauser 98 cocking piece on the firing pin and the cam notch on the bolt.

Is the notch face supposed to be 90 degrees or raked backward? Should the cocking piece make full contact with the camming surface? Does this area need to be hardened?

I have a rather hard to open bolt-- not smooth at all-- seems to "creak". Cocking piece was carving a thin groove in the bolt cam notch face leading me to believe the angle of one or the other was off. I lightly polished both surfaces with crocus paper but seemed to worsen the creak... I've never ran into this one before.

Any links, book references, or advice welcome.

Herodotus
June 26, 2000, 12:00 AM
The back of the bolt and the front surface of the cocking piece on the firing pin are the most important surfaces in operating the bolt. Both are hardened surfaces and I think they would be ideally in full and continuous contact. The depth of the hardened surfaces is not very deep, so you cannot make big mistakes in dealling with them. The fit and polish of these surfaces is crucial to making a Mauser function well and is no doubt the provence of experienced and careful craftsmen (meaning I would not fool with it myself).
What type of Mauser is it? Is it all matching?
I assume you have focused on the real problem and that there are not problems with the bolt handle, front lugs, extractor, friction on the internal bolt parts?
This is a nasty problem and gunsmiths, in my experience, don't want to fool with this area if they can avoid it. You may be stuck with it as it is.
I guess this does not solve your problems, but be careful of filing away on these surfaces.

[This message has been edited by Herodotus (edited June 26, 2000).]

George Stringer
June 26, 2000, 06:08 AM
DeBee, the thin groove in the cam notch would lead me to believe that it has lost its temper and needs to be heat treated. Since it is obviously dragging it would also most likely be the source of your creaking and hard to open problem. It would be cheaper to buy a new bolt body unless you have an accetylene welding outfit and can do it yourself. The problem there is that when you change bolt bodies you change headspace. The area needs to be heated to 1450deg (cherry red)and quenched in plain water. The water should be at least 75deg. There are a couple of assists to doing this. Templaq is a liquid that is made to paint on and allow to dry. It comes in various temperature ratings. Once it's dried you heat the part until the templaq becomes liquid again. There is also a product called Kasenite. It's a powder. You heat the part cherry red, dip it into the powder and then heat cherry red again and quench. This gives a case hardening to the part. A lot of machine shops have small ovens for heat treating. You might price that. I do a lot of heat treating of the cocking cams due to welding on bolt handles. It's part of the process. You can e-mail me if you like. I'd be happy to do it for you. George