Yeah, I've done the "bullet-swap" deal. Used to pull GI bullets out and replace with hunting bullets in '06. Or go from the old 153-grain GI down to 110- for varmints.
Do one, and check to see if the brass is springy enough for the case neck to hold the replacement bullet. If it's a little loose, just load one round at a time, to shoot. That way, recoil won't set the bullets back.
Or, you can pull the rod from your resizing die and resize about 1/16" to 1/8" of the neck; chamfer the inside afterwards.
Ah, what we do to save money! What we think is fun! Luvvit!
, Art