Thank you ,great! So , 31-is a gunmaker code , 25-yaer of the proof, 15.5 - shotgun barrel and 7,2 rifle. Now I understand those codes. I couldn't find much information about Michael Pegam, but his work seems to be pretty neat. Is it possible that shotgun chamber is of 70mm length, in 1928? Or is it 20/65? Shouldn't be calibers marked in different way in 1928, or for austrians it wasn't mandatory? Compare with German proof houses? What do you think?