I have fired all but the japanese rifles and I own a K98, a 1903, a Carcano, and a Mosin.
The 1903 is the most acurate and has the best range. The Carcano is too light for a bolt action. I would have a hard time saying between the Carcano and the Mosin which is least acurate, they are both weak. All that said I love my K98 it is an original 1942 with matching numbers and I fire it all the time. It is more acurate with iron sights than my garand, I supose because of the semi auto. I love my 1903 as well, but the Kar edges it out for me.
By the way all four are original WWII rifles and I shoot them all from time to time.