Bronze tompion in British cannon

Here’s a pic of a 4” dia. Bronze tompion in a British bronze cannon muzzle. I can post pix of cannon later but maker marks “J.Wolff” on basering are only marks so the gun was made for private party, either landowner or yachtsman. The “crest” isn’t a proper COA but a mark someone adopted. I doubt if anyone will outright recognize this but maybe someone who has mastered the Image Search can match it to something?

 

I can't see the picture all that well, but how would you pull it out, if it is tight enough to be useful and why use bronze? Are they not usually wood? It is only to keep the rain out after all.

 

Other than it's a Royal Naval Crown and Pegasus, I got nothing !

 

This one’s likely made by same company that made the one for my Dutch cannon. A 3/8” thick cast bronze plate is mounted on a hardwood plug of a bit under bore diameter and about 3” long. A piece of spring steel 1/2” wide and 3” long is inletted into plug and parallel to its length. This holds tompion in the bore. These tompions are decorative.