Gents, just my tcw but I should think it would take very little continued contact between the clips and the sides of the barrels to induce some gaping. Ergo, I don't see the real necessity for clips. After all, my 85 year old Nitro Special ain't got 'em and its still tighter than a bull's arse in fly time. Methinks much of what's been dreamed up as to the physics of simply dischaging a shotshell in a fixed breech gun is poppycock. And while I'm at it, I may as well add the poppycock of screw-in chokes, vent ribs on field guns, ported and-or backbored barrels, single triggers, beavertail forends, chrome-lined bores, et al. Now I've vented my spleen, I'm going back to the couch and the History Channel. Chops