Have owned 2 Darnes in 20 gauge with, just to be different, 29 1/2" barrels. Both guns weighed under 6 lbs, the one I still own is 5 lbs 12 ozs. The first was choked quite tightly, and was a favorite of mine for clay birds and roosters, the second has modern (bigger) bores and IC and IM chokes. I'm struggling at the pattern board to find a 7/8ths oz load that really works well in this gun, but, every 1 oz load is a winner, so far. I hate 1 oz 20 gauge loads. Isn't that what a 16 is for?
20 gauge is the rare number in Darne guns. Fewest made by far, over the years.
Best,
Ted