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5/16 socket head cap screw envelope

5/16 socket head cap screw envelope: head Ø11.91 mm (A max 0.469 in) x 7.92 mm (H max 0.312 in), hex socket 1/4 in across flats x 0.151 in deep (key engagement min), plain Ø7.938 mm shank (D max), example length under the head 1.0 in (Xem's choice); no thread, top chamfer, fillet or socket cone

Exact dimensions. True size, no tolerance added. Threads are plain cylinders at the major diameter.

STEP STL free, CC BY 4.0 (credit "Xem Studio")

Dimensions

size5/16
TPI UNC / UNF18 / 24
body D max / min (in)0.3125 / 0.3053
head A max / min (in)0.469 / 0.457
head height H max / min (in)0.312 / 0.306
hex socket nominal1/4 in
key engagement T min (in)0.151
wall min (in)0.119
fillet transition dia max / min (in)0.347 / 0.329
top chamfer max (in)0.033
bottom chamfer max (in)0.010
basic thread length LT (in)1.125
D max (mm, computed)7.938
head dia x height max (mm, computed)11.91 x 7.92
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From the full sheet

Socket head cap screws, inch #0 to 1-1/2 (ASME B18.3): head, hex socket, key engagement — full size table + models #0 to 1: every size, notes, mating features and sources. What are the head diameter, head height and hex key size of a #4-40, #8-32, 1/4-20, 5/8-11 or 1 in socket head cap screw?

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