I could be way off, but I'm doubting, that the screw is keeping the barrels attached. The obvious ways of removal, have already been addressed. Typical of any Break action shottys. However, after doing some research my own, your gun, isn't made by Ithaca. But Imported from Japan, as you may or may not have known. If that has anything to do with it. Don't know anything about Japanese shotguns. I find your problem perplexing and frustrating to be honest. Once you are able to figure the barrel situation out, please re-post and inform us of the solution.
Last edited by .50cal packer; February 12, 2013 at 10:00 AM.