Breech loading chamber for a cannon 16th century

[Matchlock]

Wax?
For sealing interchangeable iron 'patrons' for long guns and hand firearms, possibly ... we have no records of such a surviving piece though.

What we do know for sure, however, is that in early-19th service manuals (by Beroaldo Bianchini et al.), the soldier was ordered to keep the muzzle of his loaded long gun (flintlock musket) closed by either a wooden 'anti-rain' plug (Old German Regenpfropfen) fitted with a lead cover and either cloth or leather side straps (I do keep some 20 original muzzle plugs of 16th to 19th c. date in my collection).
Early-17th c. musketeers on watch used to seal and tighten the closed covers of the primed pans of their matchlock muskets by tallow (Old German Unschlitt) against both moisture and fine priming powder that was literally everywhere on their clothes ...

The huntsman of the muzzle-loading era, on the other hand, used to seal the muzzle of his gun by a hard wax plug - which of course had to be carefully removed before each shot, in order to prevent the barrel from horribly bulging or bursting ...!!!


Best,
Michl