SAKO made the Finnish Civil Guards rifles, the M-28, M-28/30 and the M-39's as well. Valmet made the Finnish armys M-27 and M-39, with Tikka making the barrels for the Army, among other barrel made and bought outside of Finland.
They took the time to put together high quality tight grouping rifles.
Near every Mosin in their inventory was tested and rebuilt untill it was accurate enough to pass, or it was parted out at the factory, the parts sorted, brought into spec or discarded, the good parts being used to build new rifles.
M28 and M28/30 barrels are found in .308 bore, as they are chambered for the shorter 7.62x53r, and when the Finns adopted the longer "D" bullet, a 200 grain spire over the previous 150 grain projectile, they marked the chambers they reamed for the longer 'D' bullet with a "D" stamp on the barrel. This, incidentally, allowed easy use of the 7.62X54r, and all the Russian ammo they could capture.
The 'D" spec 7.62x53r lets the throat except and swag the 54r'sbullet a bit, and the Finns had no problems using 7.62X54r in "D" marked M-28's or M-28/30's.
If you have an M-28 or 28/30 with out the D bullet modification, closing the bolt on a 7.62x54r cartridge pretty tough.