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North Central Kansas | I've found that twist drill bits generally cut a couple thousandths larger than the actual bit diameter measurement.
The problem with bolt or pin interference is sometimes caused by the bit cutting undersize when breaking thru the opposite side.
This will leave a smaller land that is only a few thousandths smaller than the rest of the hole. The land can usually be removed with a chamfer bit or perhaps a rat tail file.
I generally drill using the same nominal size bit as the bolt. One way to get the bit to drill a little oversize is to grind one flute slightly more than the other creating an off center point. This will cause to bit to orbit slightly while drilling and create the oversize hole.
If trying to get a hole that is the same exact size as the bit first drill it with the next size smaller. Then use the on size" bit to follow the hole and act like a reamer.
I agree that 1/32" oversize is about right for most bolt holes but sometimes a closer fit is needed.
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Drill bit to hole size question....
