.50196850"
For all practical purposes an 8mm drill is equal to 5/16 inch.
When you drill a hole in a wall, you are doing work by transferring energy to the drill bit. The amount of work done is equal to the force applied multiplied by the distance the drill bit moves into the wall. This work is necessary to create the hole by breaking through the wall material.
metal drill bit has a finer point
A titanium or cobalt drill bit.
To remove a nail after the head breaks off simply drill through the nail with an equal sized drill bit.
The precise shape and angles of a drill bit.
A tungsten coated drill bit.
That size is correctly 0.375, and is equal to 3/8 of an inch.
Drill bits not only come in fractional number sizes they also come in letter sizes. The F size drill bit is .257 thousandths of an inch in diameter. A 1/4 inch drill bit is .250 thousandths of an inch in diameter, so size F is .007 thousandths of an inch bigger than a 1/4 inch drill bit.
You need a diamond tipped drill bit to drill glass or tile.
That is a drill bit designed to remove partial drill bits that have broken in a hole