Wanted a table showing Whitworth Bolt and nut dimensions, shank, hole etc

Does anyone know where there is a table showing BAW whitworth Bolt and nut data with the following details:-
Shank/thread diameter,
Head across flats
Head across corners
Head thickness
Nut across flats
Nut across corners
Nut thickness
hole tight fit
Hole loose fit
drill size (not vital to me)
thread pitch
other thread data
another table with castellated nut data, for both types of such nut (slots in a normal nut and the circular extension that is slotted)

I can find a table with some but it needs cross referencing with a nut table, or a heads data table etc.

I am reverse engineering items from drawings with no dims or photos scaling to full size and need to assess as near as is possible the fasteners used.

I cant find a chart that has all data for a bolt and its nut.



I suppose you’ve seen this: Convert,compare all Imperial tool,nut,bolt and spanner sizes to metric.

This might be a good resource too:


and surely there is a British equivalent to:


Ask your local library to obtain a copy of B.S.916:1940 War Emergency Standard Specification For Black Bolts And Nuts.

If they cannot find that, next best would be B.S.916:1953 Specification for black bolts, screws and nuts, hexagon and square, with B.S.W. threads, and partly machined bolts, screws and nuts, hexagon and square, with B.S.W. or B.S.F. threads.


You can take a look at

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Good call @AIW, hard to find data like castle nut dimensions are there. BS1083 dates from 1965, but these probably hadn’t changed significantly since WW2.

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You are right, Jeremy. I did some more exploration on the site. It looks like, in general, the place to start is:


and then, for @Steve1, type “bs”, “bsf”, or “bsw” in the “Search entire store here” search box at the top.

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