I looked at K-var and two of the barrels are listed as 23mm the other barrel is not. There is about .040" diffference between 22mm and 23mm, so if it was a 22mm I think that it should just drop in the Romy trunnion. How much pressure does it take to remove/install the barrel or what are you using? It should take quite a bit of force to get it in or out.
It could be a cracked trunnion or trunnion on the max spec limit and barrel at the min spec limit. Do you have a mic to check the dimensions?