Shop Floor Charts

5/16-24 Tap Drill Size

Use a I drill for a 5/16-24 UNF tap — .2720" (6.91 mm).

This drill gives roughly 75% thread, the standard for cut taps. For a form (roll) tap use the larger drill from the tap maker's chart.

Nearby taps

TapDrillDecimal
5/16-18 UNCF.2570
3/8-16 UNC5/16.3125

Full tap drill chart →

Printable PDF version - Tap Drill Chart
Clean letter-size sheet for the toolbox or shop wall. Instant download, $3.49.
Get the PDF - $3.49 All 6 sheets - $12.99