The given calibre for the ammunition being 7.5x55mm, and I have seen bores measured from 7.51mm (as new) up to this 7.60mm, so I assume it is worn by nearly 0.1mm. The 7.60 is 1/3 the price of the 7.51 and my pocket is very shallow as a pensioner so cheaper is good if it will cope. Match competition shooters will want the best but I am satisfied if it will be good enough not to embarrass me in public.
West Central France. There are 3 ranges and clubs within easy reach. Ammunition is readily available and a K31 only needs to be registered (Categorie C). This is the one thing against it as I have been sticking to Categorie D weapons that need no paperwork (Snider and Martini Henry) as long as you are an adult and a club member.