Hm, i just got a batch of 8/32s from Aircraft Spruce and 11/32" fits just fine. I had a huge stock of older ones and they must have been something of an oddity, because these newer ones work fine with 11/32".
I bought 35 lbs of new 8-32 nylon locking aircraft nut for $0.25 a pound. All fits 3/8" wrench. From the outside they look just like a #10.
At the same time I bought a box of 22K of #6 tinnerman nuts and 22K of #4's.
Wish I could live long enough to use them all