Tom_H
(.333 member)
19/09/17 09:34 AM
Mauser 88 calibers?

Well, its better to be lucky than it is to be good...

Won $20 in a pin shoot
The Ruger #1 that I was gifted with (that had some light fire damage) doesn't look as if it will need a rebarrel.
And my safety glasses worked exactly as designed when I test fired the M88 from this post

Nothing terrible. Some gas slipped past the case and with glasses no damage or concerns. I was shooting a .318 196gr rn with 40gr AA4350. Case pretty smoked with a shoulder diameter that should have been .440 expanding to .460

After all of the measurements that I took I probably should have done a chamber cast first. Whatever the chambering is, it is NOT an 8x57. OAL dimensions seem ok, but the base is about .473 addition to the shoulder issue.

Any thoughts?

Tom

* don't have all of the dimensions, but those measurements match the 9.5x57 Mannlicher except in .318!?


lancaster
(.470 member)
19/09/17 02:10 PM
Re: Mauser 88 calibers?

8x57I and 9x57

very rare 10,75x57, 7x57 and 7,65x53


2152hq
(.300 member)
19/09/17 10:54 PM
Re: Mauser 88 calibers?

With the same OAL but a larger dia shoulder, I'd suspect a rechamber to 8x57 Ackley Improved or some other less known but similar wildcat of the day.
The A/I shoulder is supposed to be .456 IIRC. But being a wildcat cartridge, reamer dimensions varied. Home-made reamers and one-of builds can give you some interesting combinations.
The base dia being a bit over what you expected could have been from a recut also.

FWIW,,the idea of the Ackley Improved cartridges,,and there's just about one for every commercial round of the era,,was to be able to use the commercial parent round in the A/I chamber with complete safety. That would leave you with a fireformed A/I case for reloading.
All working nicely in a PO Ackley worked over rifle of course or one done to his specs as claimed.

just my thoughts.


DarylS
(.700 member)
20/09/17 03:49 AM
Re: Mauser 88 calibers?

.455" is the most common Ackley shoulder chamber, leaving fired brass at .454" due to case shrinkage after firing(av. .001"). This is also the shoulder diameter of the .308 family of ctgs. The shoulder angle of 40 degrees is also standard, which lengthens the body & increasing the capacity of that family of rounds from the .243 up to .358", for a slight improvement in ballistics - normally around 100fps, if held to SAAMI pressure levels.

My 9.3x62Oberndorf Mauser, as well as a factory Styer 9.3x62 rifle I obtained fired brass from, both have .455" shoulder diameters, leaving the fired cases at .454" & 78gr. capacity.


Vladymere
(.300 member)
20/09/17 12:37 PM
Re: Mauser 88 calibers?

I have a gewher 88 based sporting rifle, sold by Novotny of Prague, that is marked as 8x57 but was re-chambered (and not marked) in 9x63 Florstedt. The 9x63 Florstedt is extremely similar the .35 Whelen to the point that .35 Whelen can be fired in it.

Vlad


Tom_H
(.333 member)
25/09/17 04:07 AM
Re: Mauser 88 calibers?

I made a chamber cast and found to my dismay that the chamber had been "polished" out much like the bore. Half of the chamber is nearly parallel, and there is one spot behind the neck that is so polished that it is wider than the case behind it.

My earlier measurements were off as the case didn't expand concentrically, probably due to the low pressures.

I had some time getting the chamber cast out.

Fired a light load again but with the same gas flow past issue and a sooty side of the case.

I may actually try an 8mm 06 reamer to see it that cleans things up. I could just have it rebored to .358 and turn it into a Whelen. Too bad that the body taper on the 9x57 is the same as the 8 or that would have been a perfect solution.


DarylS
(.700 member)
25/09/17 11:39 AM
Re: Mauser 88 calibers?

You might have to re-chamber to Whelen IMP .35 - then I'd adjust the load soft from normal IMP data, Tom, as in using only standard .35 Whelen data in the IMP case for only a slight reduction in velocity, but a big one in pressure, at least below the 8x57's CIP 57,000PSI (Pezio).

lancaster
(.470 member)
26/09/17 02:47 AM
Re: Mauser 88 calibers?

the 9,5x56 Mannlicher Schönauer could be an answer


http://www.municion.org/



low pressure, fat case

compare the shoulder diameter with the 9x57 case





DarylS
(.700 member)
26/09/17 03:39 AM
Re: Mauser 88 calibers?

That would require a re-bore and rifling along with chambering.
IIRC, the 9.5x56 has a larger shoulder than the 9x57(6).

As Tom noted the shoulder expanded to .460" in his chamber - that is WAY oversize.

This rifle seems to need a re-barrel job, then it can be anything you want, within reason.

My 375/06IMP has a .460" shoulder, but seems to me, that is the "Arch" IMP case, as the "Ackley" IMP case has a .454" shoulder.


Tom_H
(.333 member)
26/09/17 11:10 AM
Re: Mauser 88 calibers?

I would love .375 but the barrel at the muzzle would only leave me .150 per side. A bit on the thin side. The barrel is just too good to waste with its exterior condition.

I will come up with something


DarylS
(.700 member)
27/09/17 02:54 AM
Re: Mauser 88 calibers?

You should be able to get a reamer maker, maybe Pacific, to come up with a chambering reamer with a .460 shoulder and .470" base, for the neck already in the case(if the bored is OK). Such a reamer could be hand fed for perfect results, as it would only be 'cleaning up' the back end of the chamber.
After that, any .30/06 based brass could be used, or even 7 or 8x57 Mauser brass - neck it straight, then neck to hold a bullet putting the shoulder where it should be, then FF.

The .005" taper per side is fine as it worked perfectly on my .375/06IMP round. I am running quite high pressures, I assume as I am getting 2,650fps with 270gr. TSX from it's 26" bl. Extraction is accomplished with little finger bolt lift and extraction.



Contact Us NitroExpress.com

Powered by UBB.threads™ 6.5.5


Home | Ezine | Forums | Links | Contact


Copyright 2003 to 2011 - all rights reserved