BS 2470 Specification

Hexagon Socket Head Shoulder Screws BSW/BSF 2470

Hexagon Socket Head Shoulder Screws BSW/BSF Thread BS 2470

Dimensions of hexagon socket head Shoulder screws, BSW/BSF Thread BS 2470

Nominal Size D A H S B T J K
Shoulder Diameter Head Diameter Head Height Head Side Height Nominal thread Size Thread length Hexagon socket size* Key Engagement
Max. Min. Max. Min. Max. Min. Min. Max. Min. Nom. Min.
1/4 0.2480 0.2460 0.375 0.357 0.188 0.182 0.157 †No.10 or 3/16 0.375 0.355 1/8 0.094
5/16 0.3105 0.3085 0.438 0.419 0.219 0.213 0.183 0.1/4 0.438 0.418 5/32 0.117
3/8 0.3730 0.3710 0.563 0.543 0.250 0.244 0.209 5/16 0.500 0.480 3/16 0.141
1/2 0.4980 0.4960 0.750 0.729 0.313 0.306 0.262 3/8 0.625 0.595 1/4 0.188
5/8 0.6230 0.6210 0.875 0.853 0.375 0.368 0.315 1/2 0.750 0.720 5/16 0.234
3/4 0.7480 0.7460 1.000 0.977 0.500 0.492 0.421 5/8 0.875 0.845 3/8 0.281

* See 2.12 and Table 7 for limits of size.
† 3/16 size apllies to BSW or BSF; No 10 size applies to UNC, All other sizes apply to BSW, BSF and UNC.
Nominal Size G I E F N M
Thread Neck Diameter Thread Neck Width Shoulder Neck Diameter Shoulder Neck Width Thread Neck Fillet Head Fillet (Above body)
BSW/UNC BSF
Max. Min. Max. Min. Max. Min. Max. Max. Min. Max. Min.
1/4 0.122 0.117 0.137 0.132 0.083 0.227 0.093 0.023 0.017 0.014 0.009
5/16 0.174 0.169 0.190 0.185 0.100 0.289 0.093 0.028 0.022 0.017 0.012
3/8 0.228 0.223 0.242 0.236 0.111 0.352 0.093 0.031 0.025 0.020 0.015
1/2 0.281 0.275 0.299 0.293 0.125 0.477 0.093 0.035 0.029 0.026 0.020
5/8 0.377 0.371 0.406 0.399 0.154 0.602 0.093 0.042 0.036 0.032 0.024
3/4 0.493 0.486 0.518 0.511 0.182 0.727 0.093 0.051 0.045 0.039 0.030