Igorrock,
I can't make out all the markings, but from what I can see, the gun does(or did)have 65mm 16 ga. chambers. If it was reproofed, it could have 70mm chambers, but it should have been remarked with a 16-70 somewhere. If you only have photos, such marks may not be obvious. I have one reproofed in Ulm, and the marks are much smaller than the original ones. As far as the rifle barrel is concerned, I guess the 8x58R Danish Krag is possible, if it was sent to your country. The 7.6 bore diameter would be pretty tight for that caliber. I think a more likely candidate is the 8x58R S&S. This caliber is more often found with a tight bore and it was loaded with a steel jacketed bullet also, so the St. m. G. mark would work for either one. These two cartridges are different enough that a chamber cast should not be necessary. You(or your friend)can directly measure the head diameter of the chamber with a caliper. If it is 8x58R S&S this diameter should be a little over .433", if it is the 8x58 Danish Krag, it should be a little over .500". I hope this helps some.
Mike
