Have any of you guys ever seen an old gun barrel (on a long rifle) that was octagonal on the outside with a heptagonal (seven sided) bore? This seems really strange to me. It's on a old long rifle that I know very little about other than it was given to my grandfather from his grandfather.....I am told the gun was "made".....Not sure what exactly that means (as my grandfather has passed so details are very sketchy)....no numbers or markings on the gun what-so-ever. Percussion cap with "set/hair" trigger lock and barrel is 40+ inches long with i'm gussing either a .32 or .36 caliber bore. It's in really bad shape, so I dare not take it apart.