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I have a 1944 manufactured Turkish Mauser with a headspace issue. The bolt closes on an 8mm field gauge. I've switched out a number of bolts and have had the same results. I have not fired the rifle. Last month I took it to a gunsmith who said that the headspace was off by .016" inch. I've asked about this on another forum and one of the answers I received was that, like Enfields, Mauser headspace can still be sloppy because the action and lugs are strong enough to withstand the play. I know that excess headspace is normally a safety issue, but I'd like to hear from any gunsmiths here as to whether they believe that .016" on a Mauser action is great enough to worry about on a rifle that may be taken to the range a couple of times a year for 20 rounds or so.

Any comments, thoughts are appreciated.

Greg
 

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Do you reload 8mm? Can probably make fire-formed brass to fit your long chamber using die(s) and materials at hand.

As mentioned above, if lugs are set back then probably not worth fixing.
This works very well. I have an '03 Springfield with the same issue as your Mauser. I use fire formed brass and neck size thereafter. The rifle feeds, functions and shoots like a dream. I've loaded the same cases 5+ times with no issues with the brass.
 

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Thanks for the info/suggestions, gents. Is there a way to tell whether the problem is lug setback or chamber without taking it back to the smith??
With the barrel off it is easy...otherwise...I feel that the Bolt will be hard to open at first [on a fired round] then get easy again...hard thing to "feel"
I fireform by using cast Boolits, seated out so far that they jam into the lands...then Necksize thereafter...
No Problems...
If you don't reload...Still no Problem...just shoot it and pitch the fired brass...
Only by reloading is "stretched" brass a Problem!!!!
 

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If it is lug setback you should be able to "feel" a bump and increased resistance as you open the bolt after firing. You can also use an articulated angled dental mirror and light source to visualize the lug seats with the bolt out.
 

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The best way to restore proper headspace WITHOUT screwing up markings, the sights and so forth. Is to remove the barrel and take off exactly 1/12 inch (Remember Mauser barrel threads are 12 per inch!) from (1) the chamber end and (2) the shoulder. That way, when the barrel is reinstalled, every thing will line up exactly as it did before. Also, because you have removed 1/12 of an inch from the chamber end of your barrel, the headspace will now be so tight that you will not be able to chamber a cartridge. This means that you will need to use a proper caliber chamber reamer and a "GO" headspace gauge to make it right. A lot of effort and fairly costly if you must pay a gunsmith to do it properly. Not worth it, unless your Mauser has a very nice bore.
 

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The best way to restore proper headspace WITHOUT screwing up markings, the sights and so forth. Is to remove the barrel and take off exactly 1/12 inch (Remember Mauser barrel threads are 12 per inch!) from (1) the chamber end and (2) the shoulder. That way, when the barrel is reinstalled, every thing will line up exactly as it did before. Also, because you have removed 1/12 of an inch from the chamber end of your barrel, the headspace will now be so tight that you will not be able to chamber a cartridge. This means that you will need to use a proper caliber chamber reamer and a "GO" headspace gauge to make it right. A lot of effort and fairly costly if you must pay a gunsmith to do it properly. Not worth it, unless your Mauser has a very nice bore.
Above is the best advise for you.
I restore and routinely rebarrel Swedish Mausers, it is easier for me to just resolder front and rear sights on the barrel to get the correct headspacing on a swede. Also, once you remove the barrel on a mauser, you will find that threads are crush fit - thus fit/sight alignment will be slightly off on a used barrel vs. a virgin replacement. Lastly, unless you have regimental armorer headspace gauges for your particular caliber - you are trying to headspace with modern (usually Forster product) gauges which are designed for MODERN rifles and tolerances vs. original Mauser 'play' in there. I have correct and original regimental gauges for the 6.5x55 and I also own Field, GO, NO-GO for the same caliber by Forster - there is a difference! If your rifle does not present headspace issues on fired brass - its likely just fine. Also, you do know that your bolt face could be worn off too, right? You could have a previous owner trying to lap locking lugs or shoulder and created some play in the process....
 

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The best way to restore proper headspace WITHOUT screwing up markings, the sights and so forth. Is to remove the barrel and take off exactly 1/12 inch (Remember Mauser barrel threads are 12 per inch!) from (1) the chamber end and (2) the shoulder. That way, when the barrel is reinstalled, every thing will line up exactly as it did before. Also, because you have removed 1/12 of an inch from the chamber end of your barrel, the headspace will now be so tight that you will not be able to chamber a cartridge. This means that you will need to use a proper caliber chamber reamer and a "GO" headspace gauge to make it right. A lot of effort and fairly costly if you must pay a gunsmith to do it properly. Not worth it, unless your Mauser has a very nice bore.
Or, since it is a mauser, you simply trim the shoulders back whatever amount is required to set the headspace to "zero", i.e., the bolt will JUST close on a go gage. Then, heat the sights (after removing the set screws) and turn them to TDC again, let the solder cool, and go shoot. This all supposes you don't have any lug seat back. Easy to verify with barrel removed.

If the bolt closes on a field gage and you don't have any setback, then yes, perhaps forming case form '06 bass would a be good idea. Back your 8x57 die off just enough so that when you size the brass you get a little resistance on closing the bolt. This in effect negates any excess headspace. Contrary to what folks believe, firing a rifle, especially a Mauser, with excess headspace will hasten setback even if none is currently present.
 

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The gunsmith is probably giving you the length its off the "Go" gauge minimum. The field gauge length, assuming the gauge is correct - there are 2 8x57 shoulder angles - should be no more than .010 above minimum and .016 is a lot. The Turks were a lot sloppier than the Germans who originally built their Mausers so I guess its within the range of possibilities

Because the controlled feed extractor holds the case back against the bolt face there wont be any lug setback from "hammering". Just compare it to another Mauser if you have one on ease of chambering and opening, especially after firing. If its badly worn it'll close too easily. If there's lug setback you'll feel the "hump" after firing as explained above.

If you don't have these evident problems I'd just reload for it, doing neck sizing only and a lighter "starter" load or a light USA made commercial round. And don't forget to anneal the cases. There's no need to fear headspace as long as it isn't a sign of wear and you have a rifle with good gas handling and wear eye protection. I've seen plenty of .308's shot from a .30-06, and that's almost a .500 inch excess headspace! No problems except the look on the shooters face when he saw the ejected cases.

I'm assuming its a 98 type action. If its an 1893 Mauser - 1944's a little late for a conversion - they do not have nearly the effective gas handling of the 98 action so you do need to be much more careful of blown cases from the excess headspace. I always downloaded the rounds by 20 to 25% for my 1893s, even with good headspace, just to avoid any chance of getting high pressure gas in my face from a blown case or primer.
 

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With new Brass nothing will happen if you lube the case with a light oil coat. No Virginia a oiled case won't increase chamber pressure
While oiling a case won't increase chamber pressure, what it will do is increase the backthrust against the bolt face, and thus obviously the locking lugs. It's best to hold the case head firmly against the bolt face (various methods) for the first couple of firings.
 

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Depends on how much oil. I suspect the pressure problems arise when a gloppy cartridge gets loaded and a little oil ends up in front of the bullet. In any case I've never oiled cartridges and the chamber and bore need to be very lightly oiled or greased after cleaning.
 

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Bolt thrust in that article is just chamber pressure X bolt face area. Oiling may add a few percent by overcoming case friction but the usual cleaning process will give you the same effect on the first round, (which is usually a flier anyway) so I guess that's why NATO proof testing does it.
 

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There is some confusion with head space effects. With some headspace the primer pushes back and pushes the case forward. That is why
primers push out at lower pressures. At something like 40,000 psi the case pushes back over the primer giving it a "rivet" look.
With a oiled case it pushes back at lower pressure. The old timers used an oiled case not to increase pressure but to insure that the
locking worked.
 
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