The Ten Kinds of Gun, Their Alloys and Powder Charges
Lengths and shot weights from bombard to scoppietto, with bronze alloy and gunpowder proportions
A text-only folio cataloguing ten species of firearm in a single running block: the common bombard, mortar, mezzana, cortana, passavolante, basilisk, cerbottana, spingarda, harquebus and scoppietto, each with its length and the weight and material of its shot. Leonardo then states five 'conditions' for well-made guns, including a bronze alloy of only three to four parts tin per hundred of fine copper, a uniform bore, a small touch-hole and a breech that narrows one-fifth toward its bottom. He closes with tables of powder charges by percentage of shot weight and gunpowder recipes of saltpeter, sulfur and charcoal graded to the size of the piece.
On this page
Ten species of gun with lengths and shot weights
The common bombard runs 15 to 20 feet, its stone about 300 pounds; the mortar 5 to 6 feet with a 200-300 pound ball; then the mezzana, cortana, passavolante (a lead ball with an iron die, about 16 pounds), the basilisk (22-25 feet, iron shot), cerbottana, spingarda, harquebus (6-ounce lead ball) and finally the scoppietto, 2 to 3 feet with a lead ball of 4 to 6 drams.
Five conditions of a well-cast barrel
The alloy should carry no more than 3 to 4 parts tin per 100 of fine copper and be well condensed; the bore of uniform width; the touch-hole small and as near the end of the breech as possible; and the breech cavity should narrow uniformly, one-fifth tighter at its bottom than at its mouth.
Powder charges and gunpowder recipes
Bombards and common mortars take 16 pounds of powder per 100 of stone shot; passavolanti and basilisks 10 percent, harquebuses 50, scoppietti 80 to 100. Powder for large bombards is proportioned 7 saltpeter, 4 sulfur, 3 charcoal; medium pieces 4-2-1; smaller ones 8-3-2; scoppietti 14-3-2.
