Mauser 98 ejection problems, check your rifles !

[roklok]

I have been shooting my recently acquired .458 WM built on a BRNO 98 military action, zeroing it and developing loads for a buff and elephant hunt next year. It had been flawless in function, as I and most here would expect a 98 to be. However, the last time I had it out, I had two failures to eject. On both occasions a brisk operation of the bolt to the bolt stop left the fired case on the bolt face. Pushing the bolt forward a bit and then retracting ejected the case. Needless to say this could be a serious issue when hunting DG.

Last night I spent some time diagnosing the issue. The ejector was sprung properly, with what seems like correct tension and no slack. I worked the bolt slowly and everything seemed to be working correctly, at least at first. I finally observed the issue after quite a bit of head scratching and repetitions. If the bolt handle is biased downwards as the bolt is withdrawn rearwards, the ejector will hang up on the bottom of the slot in locking lug and not pivot far enough outboard to engage head of case.

If the bolt handle is in a neutral position or biased upwards as it is cycled there are no issues. I tested my other three M98 rifles and none of these exhibited this problem. I then took the bolt of of my FN M98 7x57 and put it in the BRNO receiver. I was unable to replicate this problem with the FN bolt. A close examination shows the slot in the FN bolt's locking lug for the ejector is cut wider than the BRNO bolt. FN bolt on right in pic.

Extremely glad I discovered this issue before my hunt. This is a prime example of the importance of testing YOUR rifles extensively before hunting DG, and not taking for granted that a 98, M70, 550 or any other highly regarded rifle is good to go based on reputation. I would highly encourage testing your 98s with bolt handles held to the limit up and down while cycling to make sure your ejector functions properly and is not binding in slot.

Not sure how I am going to address this issue, I will probably take a small amount of material off of the bottom of bolt slot, widening it slightly. I will take a look at ejector as well, possibly thin and polish it slightly on lower edge.

 

[grand veneur]

Mauser 98 actions have a very good reputation as long as they are well-made models. Unfortunately, there were significant differences in quality in the production of these actions, especially during the WWII era where it even came to deliberate manufacturing defects. Anyone who wants to have a rifle built based on a military Mauser 98 action, needs to select this very carefully.

 

[roklok]

Mauser 98 actions have a very good reputation as long as they are well-made models. Unfortunately, there were significant differences in quality in the production of these actions, especially during the WWII era where it even came to deliberate manufacturing defects. Anyone who wants to have a rifle built based on a military Mauser 98 action, needs to select this very carefully.

Definitely !! The wartime production 98s should be suspect as a lot were built by forced labor. This one is prewar.

 

[Ontario Hunter]

Jeezus! Looks like someone used that bolt face to pound spikes! Ugh! And whoever opened it up didn't use a lot of finesse either. The ejector slot on bolt face looks chipped. I would check that spot.

 

[Ontario Hunter]

Also, if you haven't checked it yet (and you probably have), see if the ejector is flat. It's possible someone had a jamb and tried to force the action open and bent the ejector slightly. This sounds more like the problem to me because it hangs up one way and not the other depending on how the bolt handle is raised.

 

[Ontario Hunter]

I presume this bolt will not snap over on a cartridge dropped in the chamber? Doesn't appear to be sufficient bevel on the face of the extractor. A dangerous game Mauser that will not snap over is not a true DGR rifle. Not in my book anyway ... or Duane Wiebe's book. Especially if it's 3+1.

 

[Nhoro]

I would suggest rounding the slot edges and the ejector edges to a nice smooth radius. Also polish inside the slot in the bolt. Should fix the problem. It is probably a burr or rough edge

 

[roklok]

I presume this bolt will not snap over on a cartridge dropped in the chamber? Doesn't appear to be sufficient bevel on the face of the extractor. A dangerous game Mauser that will not snap over is not a true DGR rifle. Not in my book anyway ... or Duane Wiebe's book. Especially if it's 3+1.

You are correct, this one will not snap over a chambered round true to original M98 military spec. I prefer an extractor to snap over but its not an absolute deal breaker for me if a rifle is proven reliable. This one is 4+1. I may experiment with another extractor, not going to mess with this one.

 

[Ontario Hunter]

You are correct, this one will not snap over a chambered round true to original M98 military spec. I prefer an extractor to snap over but its not an absolute deal breaker for me if a rifle is proven reliable. This one is 4+1. I may experiment with another extractor, not going to mess with this one.

The military Brno vz.24 8mm I used to build my 404J would snap over in its original configuration (action had been rebarreled to 30-06 but that didn't require modifying the bolt or extractor). A local machinist opened the bolt face for 404 and I modified the extractor. Followed illustrations and instructions in Wiebe's booklet. I did have to relieve some of the extractor spring tension but I'm fairly certain it was not the original extractor. It now snaps over flawlessly. Appears to me the gunsmith who built your gun made a half arse attempt at beveling the extractor face but definitely not enough for snap over.

The fit and finish and tension of the extractor, especially the claw, can dramatically affect how smooth the gun cycles.

Here's images of my 404's bolt face and ejector slot in locking lug. My slot looks quite narrow and I've had no problems with ejector function.

Another thing to check is the bolt guide slop in the receiver tang. How much is your bolt wiggling in the track?

 

[Ontario Hunter]

It is interesting to note the locking lug for FN Mauser bolt has both corners of locking face (back end) rounded. Why? The lug only rotates into the lug slot from one direction to lock. See how Brno locking lug is only rounded on lower edge which is the face rotated into the slot when locking the bolt. Rounding both corners on FN bolt lug serves no purpose that I can see ... except maybe to weaken the strength of the locking lug!

 

[leslie hetrick]

my 24/47 98 mauser is ok. it was arsenal refurbed and looks new. it will close on a shell dropped into the chamber however.

 

[roklok]

The issue has been resolved. I removed a slight amount of material and polished the bottom of the slot between the split lug. Ejector now snaps correctly in position regardless of pressure on bolt handle. I believe through use or prior gunsmith polishing of action raceways and bolt lugs the bolt was able to rotate downwards slightly beyond the tolerances for ejector to work.

 

[roklok]

It is interesting to note the locking lug for FN Mauser bolt has both corners of locking face (back end) rounded. Why? The lug only rotates into the lug slot from one direction to lock. See how Brno locking lug is only rounded on lower edge which is the face rotated into the slot when locking the bolt. Rounding both corners on FN bolt lug serves no purpose that I can see ... except maybe to weaken the strength of the locking lug!

The FN bolt is on the right. The BRNO bolt has the rounded lug. As far as why ? Don't know. Maybe overzealous polishing by someone along the way.