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Smaller ammunition, fashioned from lead with an iron core, was also collected from the stern excavation area. Two lead balls, recovered with adhering ferrous concretions, was recognized as a type of shot characteristic of other 16th-century shipwrecks. Known by Spanish gunners as bodoques (Vigón 1947:45), these balls of composite con-struction were propelled from rapid-firing, breechloading swivel guns called versos. Each lead shot contained a cube of iron as a core, which has since completely oxidized, leaving a squared cavity visible through the lead shell. Shot 00,073, with a diameter of 4.05 cm, contained an iron cube which measured approximately 1.8 x 1.8 x 1.7 cm; shot 00,784 with a diameter of 3.96 cm, contained a cube of 3 x 2 x 2.1 cm. According to Vigón, the iron core was to be one-sixth to one-third the total weight of the ball.
Similar bodoques have been found on the Mary Rose, Henry VIII’s flagship, which sank in 1545 (Rule 1982), the 1554 Padre Island shipwrecks (Olds 1976; Arnold and Weddle 1978), a Portuguese wreck believed to date from the second half of the sixteenth century (Blake and Green 1986), as well as on the early Spanish wrecks at Highborn Cay (Peterson 1974) and Molasses Reef (Keith 1987). On the latter site, a number of iron cubes, or “dice,” cut from wrought-iron bar stock, were found, as well as a bronze shot mold.
The reasons why shot were designed in this manner are not yet fully understood, although several hypotheses have been offered. One is that they were intended to fly apart upon firing, producing multiple projectiles; or, that the iron core helped to mushroom the lead upon ignition and create a tighter gas seal in the cannon barrel for increased velocity and range (Keith 1987: 218). Another theory suggests that lead shot, as opposed to iron, created less internal wear and stress on the barrel from which they were fired (Blake and Green 1986:13). Perhaps the composite makeup of the shot creat-ed a double impact that resulted in greater damage to the target; certainly the inclusion of iron in a lead shot reduced the mass of the projectile, and may have required less powder to propel it at the same velocity as a solid lead shot (Simmons 1992:18).
Studies of composite lead/iron shot from the Molasses Reef wreck suggest that, rather than wrought or wrapped by hand, the balls were cast in a mold. Simmons (1992) noted that all of the iron cubes in composite shot from this site and others were characteristically off-center, having migrated into one hemisphere. He reasoned that the eccentric location of the iron cores resulted from the lighter iron “floating” on the molten lead within the mold before the shot cooled. To test this theory, he conducted an experiment using a bronze shot mold recovered from the wreck. After placing an iron cube into the mold, molten lead was added and allowed to solidify. Repeated replication of shot demonstrated that the iron cores did not float, but remained at the bottom of the mold in a consistant manner. Replica shot were sectioned for comparison with sectioned examples from the wreck; the positions of the iron cores in relation to the lead shells were identical, confirming that bodoque shot probably were fabricated in a mold in a quick and uncomplicated manner, with little regard for the eccentric situation of the iron core (Simmons 1992:17, 18).
Fig. 64. Composite lead shot, known as bodoques, were fashioned with an iron cube in the center, which has long since corroded away in the salt water environment.