Full scale cannons on the ironclads sets and sailing ships were made of fiberglass, designed and molded by armorer Roger Ragland. The molds were pulled from original guns at the Confederate Naval Museum Columbus, Georgia. In total, there were seven guns made: one Brooks Rifle Cannon, two eleven-inch Dahlgrens, and four nine-inch Dahlgrens, as well as three thirty-two pounders from Raglands earlier Glory (1989). A total of ten guns were used in all scenes.
If you watch carefully during the opening credits, you will see a horse fall and the rider strike his head on the ground. That was not an effect, but rather a real event where the rider suffered a head laceration and required transportation to a local hospital. There were multiple cameras used for that shot, and they continued to roll for about twenty seconds to capture the explosion effects before medics were clear to assess and treat the rider.