Don't expect to be able to order your ammo online long term.
Bill: Federal H.R. 142 – Rep. Carolyn McCarthy (D-NY)
Summary: “To require face to face purchases of ammunition, to require licensing of ammunition dealers, and to require reporting regarding bulk purchases of ammunition.”
Position: OPPOSE
From the OP statements, this gun is for a new hunter that sounds like he does not currently own a shotgun (and probably does not reload shotshells). The 16 is a great bore but it is dying. If the OP's buddy wants to have a 16, more power to him. But a 16 doesn't throw shot any harder than a 20 or a 12. For a 1 shotgun guy, it is a poor choice.
the 16 has been dying for a long time now, Im sure it will continue to linger well on into the late 2K's. I got my first 16 close to twenty years ago and ammo wasn't any more plentiful back then. in fact there are more 16 gauge options available to me locally than there were back then, especially in non-toxic.
sure there aren't loads A through Z to choose from like in the 20 or 12, but thats because the 16's a perfect all a rounder since it does one thing very well, and thats throw an ounce of shot- which by all accounts is the perfect amount for upland and most duck ventures, why fiddle with other loads? thats what the 20 and 12 are for.
besides when was the last time you heard someone discussing proper load size on this site?
from a beginners stand point 16 might be ideal, it throws a lot of shot and the recoil is more than manageable. unlike many 12 and 20 gauge loads. or 28's that don't have much recoil but don't have much of a payload, excellent patterning notwithstanding.
if mail order ammo becomes a thing of the past its going to make things more difficult for sure, thats not going to be the final nail in the 16's casket. Im sure it will suck for the vintagers who need specialty ammo, but more people will have to take up reloading, which might not be a bad thing.