Hi Patrick,
Thanks very much for that advice. I few a few old Guns like that too, but I don't think I'd be brave enough to trust pulling them apart, although I'm so tempted with this lovely old Damascus steel Barreled Fowling piece, it shoulders so nice and is in very good condition but the wood shows heavy wear. That's interesting regarding the bent ignition hole, perhaps a method of trying to maintain the pressure in the chamber as much as possible. Thanks for the tip on the clean out plug I've seen a couple on some of the breaches opposite the ignition, I was wondering if it was a good idea, thanks Ian.