Is there a difference between an army mount pipe and a spigot?

[Pipe Smoker]

I think "army mount" and "spigot" are two separate concepts. It's said that the army mount came about when a WW I soldier mended the broken shank of his pipe by fitting a sawed-off shell casing over the shank. So an army mount pipe has a metal-clad shank. A spigot bit is one that has no shoulder. Sometimes its tenon is slightly tapered to fit into a slightly conical mortise. A spigot bit on an army mount pipe often, but not always, has metal cladding too.

That said, nearly all army mount pipes nowadays have spigot bits.

Edit: Here's a Dunhill with a spigot bit that isn't an army mount:

https://www.smokingpipes.com/pipes/n...duct_id=214707

And here's a Nording with a spigot bit that isn't an army mount:

https://www.smokingpipes.com/pipes/e...duct_id=220863