Ok, so if this question is in the wrong section please move or delete. I have an old barrel I asked about recently in a different section, that from all my measuring and test fitting is a metric threaded breech. Based on the thread chaser that easily fit into the breech it appears to have been tapped for a m18x1.5 thread. Has anyone seen this before, or know of a breech plug with this threading, I haven't located one in my searches. I am guessing that I will have to build one to this spec, but wanted to reach out to you all first.
Thanks in advance,
Mike