I have been searching for a cross reference on line, but have found
none.
I just got a 1968 Borg Warner PESCO Handybook that has such a chart
"inexact and only for steel"

RC 20 ... 108 ksi
...
...
RC 60 ... 314 ksi


I am principally interested in gun design.
Anyone know anything?
TIA

--
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