Conservation Highlights: Unloading Cannon

Cannon are unloaded using special tools and a lot of patience

Author: Kimberly Kenyon, Head Conservator


X-ray of loaded cannon
X-ray of cannon, with cannon ball at bottom

La Concorde was carrying as many as 16 cannon when the crew encountered Blackbeard near Martinique. After all, it was common for pirates to attack slave ships, and La Concorde was the second of Rene Montaudoin’s ships lost to piracy in 1717. When Blackbeard seized the vessel, he supplemented these with even more guns, so it is no surprise that Queen Anne’s Revenge was still heavily armed when the ship ran aground. A pirate ship had to be ready to attack a target at a moment’s notice or be prepared to defend itself against attack. We have raised 24 of the known 30 cannon from the site. Of the 14 cannon we have now fully cleaned, 11 were still loaded.

Cannon with wooden tampion
Cannon with wooden tampion

Following the process of removing the concretion from the bore of the cannon, we can then assess whether or not there is still ammunition in the chamber. Occasionally, we can make the safe assumption that a gun is loaded by the presence of a tampion, a plug that helps protect the bore from moisture getting in and ruining the gunpowder. The tampion is removed, the bore cleaned, and unloading can proceed. Most of the time, however, the tampion is missing, and the bore is fully concreted, leaving us to guess and proceed slowly until we can make a positive determination.

A typical cannon load consists of a front rope wad, a cannon ball, a rear wad, and a paper cartridge containing the powder. Thankfully, the tampions don’t create a water-tight seal, and 300 years of seawater has seeped into the bore. Additionally, the drill we use to bore the guns is water-fed, so the bore is completely flooded and the gunpowder no longer viable, although its smell is distinct even after three centuries.

To capture and extract the load, we have custom tools created from a sturdy metal sleeve welded to a long, threaded rod. This assembly is hammered into the bore, forcing the sleeve to grab the load. Since the space around the cannon ball can be quite restricted, some force is required to hammer the tool back out, or we can use a wrench to reverse direction. We then pry the load out of the sleeve, and each piece can be conserved according to its material type.

Load extracted from a cannon
Load recently extracted from a cannon

A lot of planning and preparation goes into the process of boring and unloading a cannon, since we need the whole team to help. It only happens occasionally, but it is always an exciting day in the lab!


-X-ray of cannon C15 showing cannon ball still in the chamber. Image by NC Department of Natural and Cultural Resources.

-Cannon C15 with its wooden tampion in place. Image by NC Department of Natural and Cultural Resources.

-Rear wad and paper cartridge extracted from a cannon. Image by NC Department of Natural and Cultural Resources.

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