"well, I don't recommend it but the auto five could maybe rechambered for 2 3/4 long shells"

I know, I had mine converted around 1959. In addition to the other changes, the ejection port had to be enlarged to clear the much longer star crimped empty shells.

One of the difficulties with the 16 gauge in this country is the problem of finding ammunition. Most stores stock a very limited amount, since there is so little demand for it, and there's not much load selection, either.