Thread size

[Denver]

I'm looking to make a couple different size expander plugs and stems for a RCBS expander die, but can't figure out what the proper size tap to get for the hole in the expander button. The thread on the stem I have is a 28 tpi and mikes at .243. Is this a 1/4 x 28 with generous clearances or maybe a 12x28? Can't find any info for the number sizes to determine the proper thread diameters.

:lovebooli

[scrapcan]

holler at BuckshotHe should be able to tell you, he made me a couple and I know they are the right size and pitch.

[1hole]

Mine is 1/4 x 28.

[JRW]

I'm looking to make a couple different size expander plugs and stems for a RCBS expander die, but can't figure out what the proper size tap to get for the hole in the expander button. The thread on the stem I have is a 28 tpi and mikes at .243. Is this a 1/4 x 28 with generous clearances or maybe a 12x28? Can't find any info for the number sizes to determine the proper thread diameters.

:lovebooli

More than likely, those threads are cut to Industry standards and include a small flat on top of the thread. this allows for easier assembly of the units. looking at the thread sideways, you will most often, find a small flat on all threads. also allows the bolt/screw/etc to pass through a drilled hole.

[Catshooter]

Those measurments would be correct for a 1/4 x 28.


Cat

[Denver]

Thanks for the replies.:castmine: