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Discussion Starter · #1 ·
Hi,

Recently i was suckered into buying a gun (Mauser 71/84) which turned out to be a parts gun but while most of it is at least serviceable - i'm afraid the chamber is not. It appears to have pretty strong tooling marks that may cause brass flow into them and failure to extract, but what puzzles me the most is the length of a chamber - I don't have other 71/84 to compare and thus need some input from you guys. I would also appreciate if anyone has true dimensions of the 43 Mauser case sized or fired, or if someone had actually done chamber cast and has measurements of it.

I don't have dies nor brass so i had to use whatever i could to try and get some measurements:
- distance from the base of the chamber to the riffling is 100 mm (almost 4" !!!!)
- base at the most is .498 - .500 and not .511 as published everywhere
- shoulder (if there is one) diameter is approx .475 - it is not well defined and it's impossible to measure accurately but it appears to be somewhere at around 47 mm from the base
- the neck size is .470 - .465
- at about 76 mm chamber narrows down to .455
- barrel itself slugs nicely at .446

If anyone has good data to compare - please advise.

Sincerely,

Me.
 

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I have an original box of 71/84 ammo that has not been shot that I could get some measurements off of if that would help. If so let me know what measurements you need. Keep it simple in wording because I have never reloaded any ammo.
 

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Discussion Starter · #3 ·
I have an original box of 71/84 ammo that has not been shot that I could get some measurements off of if that would help. If so let me know what measurements you need. Keep it simple in wording because I have never reloaded any ammo.
Thank you very much - this will be great!!!

I'll make it even more simple - no words - just picture :)




Cheers,

Me.
 

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Ok lets give this a try. If I understand your print correctly #1 is .510 #2 is the center of the case before its necked down at .510 also. #3 is the dia of the case after its necked down at .463. #4 is the paper patch at .438 and #5 is the bullet dia at .423. #6 is the overall length of the whole brass case at 2.264. Hopefull this is what you need if not maybe words will work better. :)
 

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Discussion Starter · #5 · (Edited)
Ok lets give this a try. If I understand your print correctly #1 is .510 #2 is the center of the case before its necked down at .510 also. #3 is the dia of the case after its necked down at .463. #4 is the paper patch at .438 and #5 is the bullet dia at .423. #6 is the overall length of the whole brass case at 2.264. Hopefull this is what you need if not maybe words will work better. :)
FA/18,

Thank you very much!!! Your data really helps. It is almost as the chamber of this rifle was never finished since the case with such dimensions will not fit in it. On the other hand the chamber length seems way too long - maybe poor quality control?

I guess diagramm was not too clear after all... #3 body right before the necking. #4, #5, and #6 - neck at the begining, middle and the mouth, #6 - length from the base (excluding the rim) to the shoulder.

Sincerely,

Me.
 

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Chamber of 71/84

The Chamber measurements given initially seem to be the result of trying to measure the "
inside" diameters with some sort of Caliper, etc...a method fraught with difficulities....

Have you done a Chamber cast? ( Cerrometal or Wax)? If your casting medium shrinks, that may also be the reason for the "funny dimensions". (Cerrometal actually expands a little.

I doubt very, very much an "unfinished chamber"...that just DID NOT Happen in German practice ( each gun was Inspected various times during and after manufacture...not like the slapdash "Statistical" inspection system used in the US during and after WW II.

The other reason is a heavily corroded chamber ( "RUST!").

AS mentioned, the M71 cartridge case has a head of .510-.515, so the chamber clearance should e between .515-.520 or so.
The Extra lenght (lead) from case mouth to rifling is to allow for proper engagement of the projectile (paper Patched) and to clear fouling from the Black Powder...remember, this is NOT a Smokeless Powder gunbarrel.


Regards, Doc AV
BP mausers from South America are a sorry lot, either "parts Guns " or single shot only, if the mag tube is KO.
 

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Discussion Starter · #7 · (Edited)
The Chamber measurements given initially seem to be the result of trying to measure the "
inside" diameters with some sort of Caliper, etc...a method fraught with difficulities....

Have you done a Chamber cast? ( Cerrometal or Wax)? If your casting medium shrinks, that may also be the reason for the "funny dimensions". (Cerrometal actually expands a little.

I doubt very, very much an "unfinished chamber"...that just DID NOT Happen in German practice ( each gun was Inspected various times during and after manufacture...not like the slapdash "Statistical" inspection system used in the US during and after WW II.

The other reason is a heavily corroded chamber ( "RUST!").

AS mentioned, the M71 cartridge case has a head of .510-.515, so the chamber clearance should e between .515-.520 or so.
The Extra lenght (lead) from case mouth to rifling is to allow for proper engagement of the projectile (paper Patched) and to clear fouling from the Black Powder...remember, this is NOT a Smokeless Powder gunbarrel.


Regards, Doc AV
BP mausers from South America are a sorry lot, either "parts Guns " or single shot only, if the mag tube is KO.
Hi Doc AV,

The chamber has no rust what so ever and i've cleaned it to the bright metal. I've used wax and calibers with the same results. Cerrosafe i've decided not to use since the tool marks are quite deep and it will grip - i will not be able to get it out in one piece or without melting it. Chamber is smooth as baby bottom for the first 10 mm and after that are just rows of the circular tool marks - almost like a thread. BTW, today i have tried a 45/70 case formed in .43 Mauser die and it didn't go too far - it stopped on a shoulder that measured at .510 - .511. After i've annealed the heck out of another 45/70 - i was able to drive it a bit further (almost to the head) with the press - so it sized in the chamber and it measured .490 at the base dropping immediately to .480 and then to .473. No shoulder was formed on the case at all.

Anyway, if i understood you right - 4 inch chamber is ok - correct? If that is true - i can go ahead and order a reamer and be done with it - otherwise the only other shell that fits in this chamber more or less tightly - is 7.62x54R. Initially i thought someone had drilled it out to a larger caliber - bu no - it is smaller than any cartridge known to me. it's an 1888 and i'd be surprised if it was ever shot. Carried and neglected - yes but not shot.

Cheers,

Me.
 

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I got A four pack of these parts guns and got one of them to shoot.The magazine tubes were all shot through.On one of them it was obivious THAT THE CHAMBER HAD NEVER BEEN FINISHED.Being a machinist, i believe several reamers were used to do the job, not just one as is present day practace.I threw mine away, as it was useless to me.So much for famous German workmanship. I think the German's can screw up just like us.
 

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Discussion Starter · #9 ·
I got A four pack of these parts guns and got one of them to shoot.The magazine tubes were all shot through.On one of them it was obivious THAT THE CHAMBER HAD NEVER BEEN FINISHED.Being a machinist, i believe several reamers were used to do the job, not just one as is present day practace.I threw mine away, as it was useless to me.So much for famous German workmanship. I think the German's can screw up just like us.
Hi singleshotman,

Was it also 1888 by any chance? what arsenal? Mine is Spandau. Please also let me know what is the chamber length on your shooter?
As for the worksmanship - yeah Germans can screw up pretty bad just look at the Trabant or even Volkswagen for that matter - good examples of an unfinished project :).

Thanks,

Me.
 

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Dimensions of the 11mm Mauser Cartridge, according to my 1882 Kynoch catalogue, are:

Total Length: 3.025"
Case Length: 2.376"
Rim Diameter: .590"
Case Head Diameter: .515"
Case Body to Shoulder: 1.432"
Case Body to Top of Shoulder: 1.576"
Neck Diameter: .511"
Diameter of Paper Patched Bullet: .467"

Since these dimensions are contemporary to the rifle's manufacture, they should be accurate.
 

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Discussion Starter · #11 ·
Dimensions of the 11mm Mauser Cartridge, according to my 1882 Kynoch catalogue, are:

Total Length: 3.025"
Case Length: 2.376"
Rim Diameter: .590"
Case Head Diameter: .515"
Case Body to Shoulder: 1.432"
Case Body to Top of Shoulder: 1.576"
Neck Diameter: .511"
Diameter of Paper Patched Bullet: .467"

Since these dimensions are contemporary to the rifle's manufacture, they should be accurate.
Thank you very much jim7x57!

It appears though that these dimensions are for M/71 cartridge that are a tad different from M/71-84 but a great reference point in any case.
The last piece of information i need now is the chamber length (base to rifling). If what i have is comparable to others it just may have a chance to become a rifle after the reaming.

Cheers,

Me.
 

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Such M71/84 rifles were offered here in Germany too. Most of them have new-made repro stocks. Apparently someone in eastern Europe, perhaps Poland, part of which was eastern Germany until 1945, had discovered left-over parts cache of an arsenal or garrison armory, containing enough parts, both used ones and unfinished spares, to assemble, with the addition of some new made ones, several 71/84 rifles. Apparently some of the old spare barrels were never finish chambered, as a lot of these rifles were rejected by the German proofhouse for this reason. IMHO spare barrels were only chambered after installing them on an action to take care of manufacturing tolerances. As inspection was done after each step in manufacture, thes never-finished barrels may well bear the inspector's marks for material, boring and rifling. As the USA has no compulsory proof, such unchambered barrels apparently were sold there .
 

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Discussion Starter · #13 ·
Such M71/84 rifles were offered here in Germany too. Most of them have new-made repro stocks. Apparently someone in eastern Europe, perhaps Poland, part of which was eastern Germany until 1945, had discovered left-over parts cache of an arsenal or garrison armory, containing enough parts, both used ones and unfinished spares, to assemble, with the addition of some new made ones, several 71/84 rifles. Apparently some of the old spare barrels were never finish chambered, as a lot of these rifles were rejected by the German proofhouse for this reason. IMHO spare barrels were only chambered after installing them on an action to take care of manufacturing tolerances. As inspection was done after each step in manufacture, thes never-finished barrels may well bear the inspector's marks for material, boring and rifling. As the USA has no compulsory proof, such unchambered barrels apparently were sold there .
Vilen Dank kuduae!

I've suspected something of the sort. Although this rifle has the correct matching stock, butplate, barrel, receiver, screws, and rear sight with tons of inspection marks but i don't know if all of them are present - the rest of the parts does not match. The mag tube cap has no stacking rod and no provisioning for it, I also don't see any unit markings anywhere.

Cheers,

Me.
 

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Discussion Starter · #14 ·
Just in case anyone is interested...

I've obtained several original cartridges and few barreled receivers for comparison and here are the results:
Chambers of the barreled receivers measured approx 2 and 3/4 in length while mine is 4 inches long.
The wall between the extractor recess and the chamber is also missing on mine.
Obviously, the cartridge did not fit into my chamber and stops on a shoulder but a perfect fit on others.
In addition, the bolt head did not take the rim of the original cartridge and the bolt would not close with the cartridge on the barreled receiver.

So this made me look closer at the bolt head under magnifying glass - and i've finally noticed an almost invisible seam delineating an insert hard soldered into the bolt head. It appears that that the chamber of the rifle was also modified by drilling it to 4 inches and then hard soldering an insert. The soldering job was done so nicely that it is almost impossible to tell, hovever the machining on the bolt head and chamber inserts is rather rough.

To make the long story short - it appears that the rifle was converted to a .410 cartridge of some sort. I've tried firing .410 3 inch shells loaded with slugs and it did just fine although the accuracy was not that great, since the .410 slugs are underweight and undersized for the bore. Looks like reloading these shells with the original .446 bullet will improve the accuracy.

Cheers,

Me.
 
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