RonL, When I use a bolt I remove the bolts hex head after It is screwed threw the breech plug, this leaves me with a 3/8, .375 stub to shorten or cut to length on both ends of the plug. The plug still retains the same system for removal as it had originally.

Here is a photo of my Rolling blocks plug, you can see some threads exposed on the primer end. This was one of the first plugs I did and at the time I was not treading all the way threw with the tap and would jam the bolt against the end of the threads cut my the tap locking it in place. I now thread the plugs straight threw and use the end of the threads on the bolt to jam/lock the bolt in place, this leaves no threads showing. I am going to cut/fit the nose end of the plug anyway so why not cut the excess threads off, this leaves a much neater job.

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