its all about thread engagement. at small sizes like these, a few thousandths make a big difference in fit. But, considering the permanence of a scope mount, a little loc-tite makes up for alot of tolerance.
April 4, 2010, 06:55 PM
They are not listed because they are not standard screws. Basically, whoever selected them in the first place made a very poor decision by not picking something that was used for other things.
April 4, 2010, 08:49 PM
The Brownell's catalog has a chart of tap and clearance drill sizes. Surely you must have one. :)
April 4, 2010, 09:53 PM
6-48 takes #32
I use a #31 for 6-48.
I have used both and they work equally well.
April 4, 2010, 11:22 PM
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