Mauser 4000 weak ejection
- Thread starter harrygrey382
- Start date
HonestJohn
Well-Known Member
If it ejects better without the scope, that’s the issue, but a weak extractor claw spring can also cause slumpy ejection, which can be easily fixed by fitting a new spring or stretching the old one. Also with using quality brass like Norma, as I’ve also found, good brass has often better rim tolerances and makes a big difference to Sako style extractors
Smellydog
Well-Known Member
Sorry but a rifle like this is designed to function normally with a scope fitted, high or low.
The plunger or ejector keeps the case pressed right. You should by the way struggle to compress the plunger with the finger. If you can its weak.
The case is pressed right as its extracted. As soon as the case mouth clears the receiver port it should spin out to the right the plunger and extractor working together.
A strong set up as this can even dent the case mouth slightly as the case mouth jumps from the breech face to the receiver.
The plunger or ejector keeps the case pressed right. You should by the way struggle to compress the plunger with the finger. If you can its weak.
The case is pressed right as its extracted. As soon as the case mouth clears the receiver port it should spin out to the right the plunger and extractor working together.
A strong set up as this can even dent the case mouth slightly as the case mouth jumps from the breech face to the receiver.
HonestJohn
Well-Known Member
I love you man, but the Sako style extractor is famous for flicking cases up and dumping them with low fitted scopes. It may not be the case, but it’s highly likely at that scope sits very low. Have a google and you’ll find a lot of articles on it
HonestJohn
Well-Known Member
“ went through this battle with a Sako A7. Ended up having to go to high rings to fix the problem. I tried using a Leupold VXII in Medium rings, due the the turret caps on Leupies being a bit lower than most other scopes, but the brass still hit frequently. Moved to high rings, and the problem is finally solved. Since I was in high rings, I also switched scopes to a Monarch with a 50mm bell. I had tried moving a few different scopes as far forward as possible to keep the turret housing toward the front of the ejection port, but I was still having problems. The high rings was all I cold find to resolve it. This seems to be a common problem with A7's. I guess some rifles are just designed to eject brass on a higher arc than others.”
That’s from another post online -
That’s from another post online -
Smellydog
Well-Known Member
For as many videos there are illustring the issue there are as many showing normal reliable functioning
harrygrey382
Well-Known Member
Thanks for the input guys. Case is definitely not hitting the scope, ever. When moving the bolt backwards slowly it’s clearly failing long before the case ever leaves the action. Would move this rifle on before getting high rings (the whole reason I run a 40mm objective rather than 56), but it’s not the problem.
I’ll see if I can get another extractor spring - but seeing as Heym aren’t making parts I won’t be getting an OEM one, will give it a little stretch. There’s no build up of gunk that I can tell - it moves freely and is clean. But I can see now that it’s letting go very early
I’ll see if I can get another extractor spring - but seeing as Heym aren’t making parts I won’t be getting an OEM one, will give it a little stretch. There’s no build up of gunk that I can tell - it moves freely and is clean. But I can see now that it’s letting go very early
HonestJohn
Well-Known Member
Hitting the scope happens at a speed you will
Struggle to notice, take it off and see what happens. Not saying I’m right, but often you’re surprised!
HonestJohn
Well-Known Member
And try different brass!
harrygrey382
Well-Known Member
Tried a few different head stamps, no difference. Even when cycling fast I can see it doesn’t hit the scope - it fails in the same way when moving slowly that’s why I used it to explain. There is no upward trajectory of the case at all
HonestJohn
Well-Known Member
Hmmm, ok, maybe I’m wrong, it’s happened before 
however, the case is only falling out when it’s starting to clear the front receiver ring, so you need to think about that. Take the scope off and watch carefully from above what happens.
however, the case is only falling out when it’s starting to clear the front receiver ring, so you need to think about that. Take the scope off and watch carefully from above what happens.
harrygrey382
Well-Known Member
Well I can see why you’re on that path - it does seem to be a common issue and following similar Sako threads (they seem to be the most similar common details) this crops up a lot. Although people are reporting untimately even this is caused by poor extractor grip, so I think it all comes back to what Ronin said at the start. I had another good look at the extractor/case head relationship last knight and it’s definely loose - both longitudinally (towards and backwards) and fairly minimal deflection radially (sideways grip). I suspect the former is the bigger issue, so I’ll pull it out and see what I can do, either by bending or TIG, filing and rehardening itHmmm, ok, maybe I’m wrong, it’s happened before
Ronin
Distinguished Member
Very careful application of dremel and a backed cutting disc (wear saftey glasses at very least) May allow you to dress the inner surface ,,,,
If you’ve access to a d bit grinder (Deckel or similar) then a tool could be made from a carbide stub to re dress the inner surface of the extractor
Fiddly but not impossible to do
Shame it took a page of, “ it’s this, No it’s that” to come full circle
️
The beauty of opinion and discussion though
If you’ve access to a d bit grinder (Deckel or similar) then a tool could be made from a carbide stub to re dress the inner surface of the extractor
Fiddly but not impossible to do
Shame it took a page of, “ it’s this, No it’s that” to come full circle
️The beauty of opinion and discussion though
harrygrey382
Well-Known Member
Right - I think I get the process. I don’t have access to a D bit grinder, only a mill and a lathe. But I’ve got a reasonably steady hand, I might practice with a dremel cut off wheel and see how it looks. I guess the closer the radius to a case head the better…Very careful application of dremel and a backed cutting disc (wear saftey glasses at very least) May allow you to dress the inner surface ,,,,
If you’ve access to a d bit grinder (Deckel or similar) then a tool could be made from a carbide stub to re dress the inner surface of the extractor
Fiddly but not impossible to do
Shame it took a page of, “ it’s this, No it’s that” to come full circle
The beauty of opinion and discussion though
Oh and - I never doubted what you wrote, but it was also interesting to get a few other opinions!
Ronin
Distinguished Member
Wasn’t written as critique - more observation that the discussion has come full circle
Sometimes the word (meaning) is lost when typed
Yes - case head diameter cutting tool or radius of same would assist in dressing the extractor
You could make something on the lathe and mill but easier with toolpost or d-bit grinder to do so out of carbon
You may find a diamond needle file of sufficient profile and size that may be suitable too
Sometimes the word (meaning) is lost when typed
Yes - case head diameter cutting tool or radius of same would assist in dressing the extractor
You could make something on the lathe and mill but easier with toolpost or d-bit grinder to do so out of carbon
You may find a diamond needle file of sufficient profile and size that may be suitable too
Last edited:
harrygrey382
Well-Known Member
File would leave a flat profile though? How about a 10mm carbide 60° dovetail cutter coming in at an angle?
This is as micro as my phone camera can do
harrygrey382
Well-Known Member
So I dressed the undercut a little with a small slotting disc, then releaved the area beneath the claw to allow it to sit closer to the centre (eg primer). Reassembled and this hasn’t made much difference- possibly a slight improvement but still not great. Now I’m thinking of heating it up and bending the end in a little which will both give more longitudinal grip (reduce length) and improve the angle. If this doesn’t help I’ll build it up with TIG and 1045 filler rod and machine a new groove, maybe with a dovetail cutter
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