You say the rifle shoots well now, so I personally would be very leery of doing anything with the barrel. There is a lot of voodoo magic attributed to the steps on those mauser barrels.
I have said this before, and no offense intended, but I think making a rifle light and short barreled for a beginning shooter is a mistake. The heavier a rifle the less it recoils, and the longer the barrel, the less muzzle blast experienced. These factors help both the young and old shoot better.
My first hunting rifle was an '03 springfield and I would have sooner complained about my grandmas cooking than about my new rifle. Have your boys actually complained about the swedes weight? Also, depending upon the degree of sporterization, the swede as it is might be easier for your boys to shoot now than the short Turk. Just a few thoughts.