Mauser 98 cocking mechanism?

[Creedmore]

Any experienced Mauser 'smiths in the house? I have a .25-06 built on an Argentine Mauser 98. Gunsmith friend-of-the-family built it for me 20 years ago. It's a bonafide tack driver. Went out to check the zero last weekend and while I was cleaning, I noticed something that I don't remember seeing before.

With a snap cap in the chamber . . .

1. Dry Fire.
2. With muzzle pointed up (or just slightly up) from horizontal, rotate the bolt, and firing pin is re-cocked.

3. Dry Fire.
4. With muzzle pointed downward, rotate the bolt and the firing pin is NOT recocked.

What is wrong with this picture? Something doesn't seem right.   

[John Traveler]

I just played with an available M98 action to duplicate your problem.

It's fairly common with the cock-on-opening M1898 mauser to have the trigger or sear movement stick due to dried oil, grease, dirt, etc.  Normally, working the bolt vigourously is enough to jar the trigger sear back up to be ready to engage the bolt sear. 

A fairly common problem with surplus mauser actions such as yours is that the firing pin sear and the trigger sear develop mismatched or burred surfaces, causing them to "snag" during slow bolt manipulation.  Inspection and a few strokes using a honing stone will correct this.

And finally, wear of the receiver camming surface against the root of the bolt handle can cause failure to cock on opening.  This wear affects the sear engagement, and is particularly common when bolts are mismatched to receivers.

Any or all of these factors can cause the failure to cock.  Disassemly, cleaning, and inspection will help you to determine which it is.


HTH
John

[gunnut69]

What type trigger is installed. Aftermarket triggers can fail to reset if gunked up or set with too light a trigger return tension. Also they can come loose and fail to reliably reset. A tear down and cleaning are likely to either solve the problem or at least define it's cause..

[Creedmore]

I removed the bolt last night and took a closer look.  There was some old oil buildup on the bottom side of the bolt. 

However, after inspection I think my trouble is with the sear-sear contact.  Judging by the coloration and shiny polished spots from wear, the bolt sear and trigger sear look like they are not getting uniform contact.  One corner of the bolt sear seems to be very polished and almost rounded off. 

It has a Timney trigger installed, set at 3lbs if memory serves.  I'll put my gauge on it tonight to double-check.

Anything I can do short of taking it to a gunsmith?

Thanks for your help!   

[gunnut69]

It's likely the trigger is failing to reset after the striker has been withdrawn. The striker is cocked by the action of a cam machined on the rear of the bolt body.. This presses the striker to the rear as the body is rotated. If it is not drawn back far enough the trigger sear won't reset. Is the striker drawn back when the bolt is rotated and just falls when the bolt is rotated back into battery? An uneven wear pattern would seem to indicate a lot of wear, not unusual on the 98. But that doesn't explain the muzzle up/down difference in cocking response. Clean everything and retest to see if the problem is solved. Also check the trigger sear for it's resetting ability. A finger can be used to press down while a pull on the trigger blade should release the sear allowing the finger to move the sear forward and down. A new cocking piece may be in order or a little work on the striker sear/trigger sear inter face..

[Creedmore]

Now that the holiday chaos is over, I took the barreled action out of the wood.  Hasn't been out of the wood in I don't know how long, since I bedded it and my gunsmith installed the trigger. 

Short story long, the 3 trigger adjustment screws were covered in locktite.  The screw in the front of the Timney trigger - that keeps the trigger in place and tight against the receiver, was NOT coated in locktite and had worked its way loose over the years.

A drop of locktite, few turns of the allen head and she's good as new.