GEW 88 Enigma

[Patrick Chadwick]

I think Claven2 has got it nearly right.

But

First thought would be caliber change to a rimmed cartridge.

is, I think, the correct answer.

1) Dings on wood but none on metal = metal has been refinished. I am quite sure about this, as I have such a rifle in my possession!

2) Shoulders have been ground off the bolt = chambering alteration, at the very least to a rimmed cartridge. But not .303 - the bore would be far too loose, and it looks as if it is an original German barrel, if not necessarily the original barrel.

The simplest explanation is that it may have been modified for 8x57 IR - the rimmed version of the 8x57 I used for break-top hunting rifles. Please note I not IS - in other words the original Gew.88 bore/groove dimensions. So .323 bullets would be too fat - you need the .318 diameter.
Dimensions and load info for the 8x57IR can be found in the Dynamit Nobel Wiederladen - the "blue book".

Simple test: see if an 8x57 case can be chambered. If so, QED*. Well, almost, but please note that there is also an 8x57 IRS - the rimmed version of the later 8x57IS.

Safety note 1
In this case, you MUST slug the bore.
Bore/groove 7.80 / 8.07 mm = original "I" bore
Bore / groove 7,92 / 8,20 = "IS" bore

Safety note 2
The rimmed versions of 8x57 I and 8x57 IS have much a lower Pmax than the rimless versions.
857 I - 3800 bar
8x57 IR - 3200 bar
8x57IS - 3900 bar
8x57 IRS - 3300 bar

So please do NOT try any K98 loads in this old action! Before someone writes in to point out that the rifle was originally made for the 3800 bar of the 8x57 I: yes, I have worked that out myself, but the reworking of the bolt means that the weak point is likely to be the base of the cartridge.


Patrick

*8x57 cases are too wide at the shoulder to fit into a .303 chamber. And a touch too long. But with worn military chambers one is never quite sure, and I have seen a 308 pushed into a 30-06 chamber - which should also be impossible. So Claven2's recommendation to make a chamber cast is sound advice.