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Q drill bit size
Q drill = .3320 in = 8.43 mm. Closest metric drill: 8.4 mm.
Taps that use a Q drill
- 3/8-24 UNF: about 79% thread
Nearby drill sizes
| Drill | Type | Inch | mm | Difference |
|---|---|---|---|---|
| 5/16 | fraction | .3125 in | 7.938 | -19.5 thou |
| O | letter | .3160 in | 8.026 | -16.0 thou |
| P | letter | .3230 in | 8.204 | -9.0 thou |
| 21/64 | fraction | .3281 in | 8.334 | -3.9 thou |
| Q | letter | .3320 in | 8.433 | 0.0 thou |
| R | letter | .3390 in | 8.611 | 7.0 thou |
| 11/32 | fraction | .3438 in | 8.731 | 11.7 thou |
| S | letter | .3480 in | 8.839 | 16.0 thou |
| T | letter | .3580 in | 9.093 | 26.0 thou |
1 thou = 0.001 in = 0.0254 mm. Drills a few thou apart are usually interchangeable for clearance holes, but not for tap drills or reamer pilots.