A single example of cast- iron shot, of larger caliber than the verso shot, was found near the other balls. Its diameter, 6.23 cm, suggests that it may have been ammunition for a heavy wrought-iron gun. During the late 15th and early 16th centuries seige artillery went to sea for the purpose of bombarding enemy ships. During an age when the technology for casting large iron objects had not yet been developed, cannon tubes were hand wrought, or built up from smaller, forged pieces of iron welded together to form a reinforced barrel with a corresponding powder chamber. Essentially, a series of long, flat iron staves were laid up and welded parallel around a mandrel to form a tube, open at both ends. Then, a series of alternating iron sleeves and hoops were slid over the tube (barrel) and welded in place to provide reinforcement to the barrel. At least two of the hoops were fitted with lifting rings to facilitate moving and mounting the weapon to a wooden carriage. Powder chambers that mated to the breech end of the barrel were constructed in a similar fashion; a single gun may have had several interchangeable chambers to facilitate rapid reloading.
The most common type of built-up wrought-iron heavy guns found on 16th-century shipwrecks are called bombardetas. Examples from Mary Rose , the 1554 Padre Island wrecks, the Highborn Cay Wreck, the Molasses Reef Wreck, and the St. John’s Bahamas Wreck were found with their corresponding breech chambers and solid-iron ammunition. Bombardeta barrel lengths varied between 0.64 m and 2.65 m; bore diameters ranged from 7 cm to 11 cm; a pair of matched bombardetas from Molasses Reef exemplify the type, measuring 2.65 m in barrel length and 8 to 9 cm in bore diameter (Keith 1987:181)
The single iron shot from the Emanuel Point Ship may have been intended for use in a small bombardeta; its diameter (6.23) is almost nine-tenths the diameter of the smallest bombardeta bore. Alternately, it may have been intended for a shorter, smaller type of wrought-iron built-up cannon, called a cerbatana. A weapon like this was noted to have been on the Molasses Reef Wreck site, but was removed by treasure hunters before archaeologists could study its features (Keith 1987:182).