One interesting point is that the Amphenol web site shows the standard type
bulkhead mount connector - the UG-1094/U type - but has no spec on the thread
or the thread tolerance. There probably is a MIL spec on the thread tolerance,
but I suspect that you would have to buy proper MIL spec connectors to get it.
The standard BNC thread is 3/8-32 UNEF: from memory, it's a 2A tolerance. I
find that 3/8-32 ME (Model Engineer) thread tap and die are close enough for
all practical purposes, even though they are a 55 degree Whitworth form rather
than the 60 degree Unified form thread.
It's maybe worth checking the diameters of the connector and the nut.
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