Hi Matchlock,
I'm surprised and impressed, I would have assumed that given the age of the pieces metal fatigue and oxidation would have taken a greater toll on their ability to be fired. If you Google 'Ulrich Bretscher's Black Powder Page' there are interesting articles on manufacturing black powder and on the making and firing of 'Handgonnes'. How accurate are these old guns?, I've always thought that on many occasions it would be more dangerous to be behind the gun rather than in front. Nice to know that some things were built to last.

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My Regards,
Norman.