From: "M H Stein":
Burroughs used this sort of thing in some old
patchboards; I wonder if
by chance they're the same size? The diameter of the hole is a tight 1/16"
drill bit FWIW; the tapered pins are tinned though, not brass.
My DEC trainer fits a 3/32" bit in the holes pretty well. 1/16" just
floats around in there.
Vince.