I have an old Dixie Gun Works 15/16" straight octagon barrel with 5/8" 18 TPI Thread pattern. The problem is while the breech plug fits the barrel threads fine with no shake from side to side, it falls short of the internal shoulder. The length of the plug to from the face of the threaded plug to the front edge of the tang portion is .5781" with the depth of back end of threaded barrel being .7812" to the internal shoulder. This means the plug in the barrel leaves about .2031" of exposed threads within the barrel, which I assume can be a fairly serious safety hazard. What can I do to possibly remedy this problem? Should I (a) order a new breech plug and hope for the best regarding the thread length of the plug in being long enough to jut up against the internal shoulder or (b) should I get a machined plug blank and use the appropriate die to cut the threads? If I do the later I would still have to be concerned about the plug length being long enough to reach the internal shoulder. Has anyone here ever dealt with this kind of problem and if so how did you go about solving it? Thanks in advance for any replies.