Dating of chambers for breechloading cannon

[fernando]

Rather complex subject indeed, taking into account a vast range of considerations like time line between different nations being distinct, with some adopting certain types and others not, and each one in its own period. The universe of typologies is huge and so are the locking systems, handles and all that.
See how slim is a "Esmerilhão" of the beg. 167h century, exhibited in the armoury of the Ducal Palace of Vila Viçosa, with a 3 cms. caliber, total length 186 cms. with a breech of 44 cms.
Then we have two of the seven bombard chambers used in the siege of Baza by the Spanish Catholic Kings in 1489. These have a caliber of 20,5 cms and a length of 142 cms.
An at last we have a chamber from the end 14th - beg. 15th century, in exhibition in the Portuguese Navy Museum. With a weight of 1450 Kilos, a length of 1,5 mts. and an exterior diameter of 42 cms. (38 cms. at the muzzle), it would have served a gross bombard or "Trom" of some 4 to 5 mts. length and a muzzle diameter of circa 1,5 mts.

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