I'm upgrading wiring in an older home which originally had ungrounded
two-wire fabric-sheathed cable. I replaced it with 12/2 with grounding
wire in a few circuits.

The existing handy boxes (is that the right word for outlet boxes?) are
not as big as the ones currently being sold.

For a middle of the run receptacle, I'm looking at 4 wires + ground +
grounding wire nut (the one with the pass through if you've seen them)
and clamps in one of those boxes which is 12 cu in or less, and I can
barely close up the outlet cover.

I'm wondering, is it required to change the outlet boxes to the bigger
14 cu in (or bigger) boxes when I upgrade the wiring? That would be
much more work than I had originally anticipated.

Thanks.

--
Himanshu