Why would you take out the tube and shoot with it out. Have a gunsmith check the tube threads for damage before firing again. The damage may already be done and the barrel is no good if they wont screw in easy or its possibly cross threading because of the lead from slugs wiping out the threads. That is proably the quickest way to ruin a barrel. If still good get a cyl bore or imp.cyl. tube for it. The tightest you can go with slugs is modified. Full is a little too tight of a constriction for some slugs. The rifled tubes are good also but if you have a smoothbore barrel try the Federal Tru ball or Brenneke. They are the two that are pretty good with smoothbores.