Yes, with the right press fixtures the barrel can be pressed out of a finished rifle.  If you are removing the trunnion from a cut receiver it is best to press the barrel out first so you don't drill into it.

I used a 12" socket extension to press one out - it worked fine.  I just put a nickel on the barrel and pressed it out.

Quoted: Quoted: I used a 12" socket extension to press one out - it worked fine.  I just put a nickel on the barrel and pressed it out. was this from a trunnion and FULL reciever??? I would like to ONLY remove the barrel of a FULLY built rifle.

Of course you have to remove the stock also to do this.

Yes, you can remove the barrel without removing any rivets or trunnions.

Remove the stock / bolt carrier/trigger/hammer/etc., press out the barrel pin, set up the receiver with the barrel pointing down on a 12 ton press supported with appropriate blocks, place a couple of nickels on the end of the barrel, put a 3/8" 12" socket extension on the end of the barrel using the nickels as buffers, press the barrel out.

The socket extension is used with the square end towards the press.  It being tough and fairly narrow will stick up over the end of the rear tang when in place at a slight angle - the barrel will press out fine with the extension at an angle - just take it slow.