It's kind of a silly argument. There are M39's that shoot sub-MOA, and K-31's, and M96's, and K98's and 03 springfields. There are Arisakas that can shoot that well, too.
The question is too vague. What it should be is over the course of the entire manufacture of a single variant, which model was the most consistently accurate?
In that light, a rifle like the K31 is very good. Or, obviously, it's grandfather the 1911SR. The Swede 96 is also very capable, the M27 Finn Mosin is legendary, on and on.
It's also very important to remember how much of an impact good ammo made on these guns. The K-31's ammo was nearly match grade, always. Not so for the Swedes, or the Japanese, so their rifles in service tended to be average but on the range with good ammo were phenomonal.