[georgeld]

I don't recall ever reaming or boring one out.

I did turn some off the bottom of at least one once.'

It was quite hard and I used a carbide lathe bit.

Once the: Case hardening was cut thru, it was just

steel and easy cutting.

The term "Case Hardening is misused for coloring gun actions.
The real meaning is. The outside few thousandths is hardened,

inside that is plain steel hardness. It actually has nothing to do
with coloring.

Instead of arguing with me over that, read some metalurgy books
and learn.