Just remember I was at a gunshow about six months ago and saw a bunch of new 16 bores. I was looking for a Browning Superposed and saw quite a few Browning 16ga O/Us, also, believe Remington pumps and automatics. IMHO, a fad.
The 16 was popular at one time but when you try to buy a box of shells they are about $10, if you can find any. As Dave said, the different gauges used to be tailored to the cartridges so a 16 ga was actually 3/4 the size of a 12 ga and a 20 was 3/4 the size of a 16. That is not the case any more where the 16 is built on a 12 action for economy.
The Browning O/U MAY BE built smaller than a 12 but I did not look at them all that hard because I was not interested in a 16. Make mine a 12 and I'll load it light if I want less performance.
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