The Model-39 with a standard bore of .312" is one of the most accurate battle rifles ever fielded. Before it could be put into service, each one had to be capable of a 1.3 inch group at 100 meters. When they were sighted in at the armory they were fitted with individual front sight blades of different heights as required for each rifle. The height was so stamped on top of the wide blade post sight and at the sight base. IRRC, the Model-39 was the only battle rifle fielded in WW2 that front sight was easily adjustable for windage in the field. On the front sight left windage adjusting screw, it is surrounded by 8 dots, each dot represents one minute of angle at 100 meters. The rear sight has small lightly stamped crosses beneath the left and right sliding surfaces. And it was woe to any Finnish trooper who dast put a file to either the front or rear sight.
My Model-39 was built on the receiver from a Russian Mosin Nagant made in 1914, captured by the Germans (receiver so stamped) in WWI, then sold or given to the Finns. All the Finnish barreled rifles from 1918 until the 1950s were built on a captured or bought Russian MN receiver, as the Finns never made any receivers. If the ammo is any good, my Model-39 and Eastern Bloc rounds with the superb issue iron sights, can shoot one inch groups all day long at 100 yards.
