I think I remember reading once that had the A&D been developed before the sidelock, the sidelock never would have been invented.
This was of course purely speculation on someones part. It could of course have been quite easily proven had the A&D shortly made the sidelock obsolete. This I think we all realize did not take place. There are in fact even at this late date many (Myself Included) who prefer a sidelock above an A&D.
There were also Boxlock muzzleloaders, though not strictly speaking A&D actions.
