I have a new version of Savage 111 trophy Hunter with Accutrigger .300 Win Mag

want to know what is the options I could convert to;

I am new and do not know too much now and I want this information ASAP...

I know since most of savage parts are exchange able and that .308 / 30-06 / 300 Win Mag / 300 WSM are acuatlly same in diameter,......which means the barrel diameter are the same...

so... ....silly question, for savage 11/111 in theses calibers , .308 / 30-06 / 300 Win Mag / 300 WSM , are their barrel the same and exchange able ?

or if I change to one of these , I do not need a new barrel ??

I would like to go to 300WSM if possible, what parts I need ?
or if I go to 308 / 30-06, what parts I need ?

Thanks!!!!!