8x57R (either JRS or JR)
Either a .318 or a .323 bore
Mine is a .318 bore, and the J is really an I, so for mine it is an 8x57IR

15 grams is 231.485 grains


https://www.sportsmansguide.com/productl...c=96&s=2884

Take a look here on manufacture dates

And measure the 12 gauge chambers, they may be 65mm as I could
not read the marks in the photos.

Made 1912 to 1939 but should get more exact with better pictures. (see Item #20)

Looks like 1136 or November 1936

Mike

fun reading:
http://www.germanguns.com/upload/archive/index.php/t-584.html

Last edited by skeettx; 04/18/19 06:55 PM.
USAF RET 1971-95 [Linked Image from jpgbox.com]