Stan I know this information is rather to late but on second thinking my post I should have added a little more information. Other than guns my other love in life is making clocks and we clockmakers have solved the screw thread size problem a long time in the past. To this end we have screw plates that go up in very small increments unlike engineers taps and dies that increase in standard size and screw pitches.
In the photograph is a clockmakers screw plate with its set of taps, from memory that particular one ranges from .7mm to 2mm in 14 steps they look expensive but the one in the picture costs 13 and you can find them on e-bay. They are made from carbon steel not high speed steel so a limited usable life though over the years I have gathered a collection of these of sizes you would not thought possible, the thread is only standard to the taps that come with the plate in other words just a screw thread. The one thing that sets this system above every other method of generating a thread is that no matter the diameter of a thread needed this system will produce it for you. These plates are still found in instrument and clock workshops because they work to produce a thread and a matching threaded hole when all else fails.
