Bob,
My 16 gauge double, an Ithaca Nitro Special, is actually my non toxic shot shotgun, oddly enough.
I had one of those.
It was both my first 16 gauge, and my first lesson in trying to shoot a gun that didn't fit.
It was something around 2 1/2" DOH, which is about 1/2" lower than my ideal. Nice gun, other than that.
It went down the road fairly quickly.
2 1/2” is a fairly modern drop dimension. Mine is 2 3/4” and it is a fairly late Nitro, 1938 vintage. I can shoot 2 3/4”, but, those lovely English doubles that feature 2” of DAH are out of my league. 2 1/2” is about perfect for me.
The Nitro is ‘sorta an implement, a bit of a reminder of the times my ancestors lived through, Americana at its purest. I have nicer and more expensive guns, but this one fits some hunting that I do, so, I keep it around.
Best,
Ted