Tap the muzzle for a grease zirk, use a 4000 psi grease gun to force it out. Will require the barrel be cut off beyond the thread and recrowned…this is a modified version of a Canadian gunsmith that used a driver in the tail stock on his lathe that had a cone that would seal at the muzzle and a grease zirk on the side. Pretty slick. I used that once for a similar barrel someone f’d up the same way.
