1949, not knowing the current outside dimensions, it's hard to say. However, my brother has re-contoured barrels to make them "slimmer". It is a VERY slow process as you can only take very shallow cuts. Otherwise the barrel will start to hold heat and expand lengthwise. Being that this is done on centers the extra length having nowhere to go will bow the barrel. Then it's junk.
What is the muzzle diameter now and what do you want to end up at? That will help estimate the time involved.
