COUNTERBORE SIZE CHART
INCH CAP SCREW				METRIC CAP SCREW
SCREW SIZE	HOLE SIZE	COUNTERBORE DIAMETER	COUNTERBORE DEPTH	SCREW SIZE	HOLE SIZE	COUNTERBORE DIAMETER	COUNTERBORE DEPTH
0	0.073	0.125	0.073	M1.6	1.95mm	3.5mm	1.95mm
1	0.089	0.156	0.089	M2	2.4mm	4.4mm	2.4mm
2	0.106	0.188	0.106	M2.5	3mm	5.4mm	3mm
3	0.120	0.219	0.120	M3	3.7mm	6.5mm	3.7mm
4	0.136	0.219	0.136	M3.5	4.2mm	7.2mm	4.2mm
5	0.154	0.250	0.154	M4	4.8mm	8.25mm	4.8mm
6	0.170	0.281	0.170	M5	5.8mm	9.75mm	5.8mm
8	0.194	0.313	0.194	M6	6.8mm	11.25mm	6.8mm
10	0.221	0.375	0.221	M7	7.8mm	13.25mm	7.8mm
12	0.246	0.406	0.246	M8	8.8mm	14.25mm	8.8mm
1/4	0.281	0.438	0.281	M10	10.8mm	17.25mm	10.8mm
5/16	0.344	0.531	0.344	M12	12.8mm	19.25mm	12.8mm
3/8	0.406	0.625	0.406	M14	14.8mm	22.25mm	14.8mm
7/16	0.469	0.719	0.469	M16	17mm	25.5mm	17mm
1/2	0.531	0.813	0.531	M18	19mm	28.5mm	19mm
9/16	0.594	0.906	0.594	M20	21mm	31.5mm	21mm
5/8	0.656	1.000	0.656	M22	23mm	34.5mm	23mm
3/4	0.781	1.188	0.781	M24	25mm	37.5mm	25mm
7/8	0.906	1.375	0.906	M27	28mm	41.5mm	28mm
1.000	1.031	1.625	1.031	M30	31mm	47.5mm	31mm
1.250	1.312	2.000	1.312	M33	34mm	51.5mm	34mm
1.500	1.562	2.375	1.562	M36	37mm	55.5mm	37mm
1.750	1.812	2.750	1.812	M39	40mm	59.5mm	40mm
2.000	2.062	3.125	2.062	M42	43mm	64.5mm	43mm