Not in our lifetimes. 8s have been illegal in the US for quite some time (10 gauge is the largest legal gauge.. at least for waterfowl). I thnk the limeys can still use them if I'm not mistaking. There are still a few 8 gauges (that shoot modern type shot shells) around. You don't see many in the states... since you can't hunt with them, and target shooting with them is somewhat of a joke.

Most of the old "big" bore guns were muzzle-loading, blackpowder "fowling pieces". Some of them weighed in excess of 25 pounds and were acctually shoulder fired. 8 bores and some 4 bores used up to 6 ounces of shot, which is almost three times as much as the most packed 12 gauge 3.5" turkey load. The smoke was something to see... and reports read that a shooter would hear the pellets hit the bird, and taking birds out to 100 yards was fairly common practice!

FC Selous used a 2 bore with a solid 1/2 pound ball as a shoulder fired elephant rifle. The recoil was so severe that he had to wrap the stock with a "green" elephant ear and bind it tightly so that when it dried it would re-enforce the stock. He used a "handful" of black powder, and once wrote on being distracted and double charging it. He was thrown from his mount (elephants were often hunted from horseback in those days). He developed a terrible flinch from the feroccious recoil of the thing.

Punt guns were (and in some places still are) used to raft shoot (ducks on the water.. also known as a ground swat, skilled shot or water swat) waterfowl in the market hunting days. Often done at night, on open water out of a scullng type boat powered by oars. The guns were usually about 10' or more in length and were fastened to the boat itself. The boat was really built around the gun. It fired large amounts of grape shot... which is a technical term for whatever the hell you can find that is small enough to be numerous and large enough to kill a duck or goose. There is a video on youtube of Tom Knapp shooting one.... pretty impressive.

A few buddies and myself built one in high school in our metals/shop class. I'll spare you the story. They are simple and effective, though we didn't use it for its historic purpose... mostly it was just cool.