Ideologist said "It really depends on how the shaft was threaded. It probably fits. You may need to run a .300" reamer through the shaft opening, but I've never had to do that unless the shaft was undercut for a tight fit on a 60 degree thread . . . . "
And to your point, the threading is exactly the same, 10 threads per inch. It is the minor diameter that is different, hence the possible need for a reamer.
My 2 cents,
Gary