Perhaps the OP was referring to this cue.^^^ say what?
xcueguy nailed it.
and why is this posted in the for sale / wanted forum if nothing is being sought or sold?????????????
Perhaps the OP was referring to this cue.
FWIW, I've never seen an It's George cue with a 5/16-18 thread either.
It's George pin size is .302" x 14tpi which slightly smaller than 5/16x14. A 5/16x14 shaft will fit on an It's George butt because the size difference is not that great but an It's George shaft will not fit on a 5/16x14 pin. The .302 diameter hole is too small.
I have tried to screw an It's George shaft onto an 5/16 pin and it's not close. The pin would not fit into the shaft hole enough to engage the threads. 5/16 equates to .312. The .010 difference is noticable.
I just measured the minor diameter of some George inserts and standard inserts. The minor diameter of the George inserts are actually quite small. The difference in minor diameters of the inserts is more like .020, twice the difference of the major diameters of the two pins. I am a little surprised at that.
Maybe it IS the hole of the insert (minor diameter), or maybe it is all 3 measurements, the minor, major, and thread pitch diameters. <shrug>
In my first post, I was partly confused by your reference to the .302 hole in the shaft. I even had to edit my post because I was naming things incorrectly. The minor diameter of my George inserts is about .236.
Kelly