Yeah a set of 6 pound 8 gauge barrels would be light for sure. I think the barrels on my Churchill might weight 12 pounds by themselves. I've shot it at geese and when you're coming up on a bunch of decoying pinkfeet it don't feel that heavy.
Lots of guys shot 8 gauges for wildfowling back when they were legal. They for sure weren't strickly a tool of the market hunter. I just picked up the new book about Carroll's Island Hunting Club and it seems like all those boys used were 8 and 4 bore guns.
Destry