Harry, you did well with your prompt, especially by not defining "best." Lots of ways to interpret the word, but today, at least for now, I'll say the best gun(s) I have had are two that have served me best, in other words, consistently took birds for me over time.
Here they are:
A John Dickson and Sons boxlock 28 bore that was my constant companion over the course of many years -- years when there were birds in Missouri. I have not used this gun in some years, but it still has accounted for the most birds of all kinds (except dove, turkeys or waterfowl), including pheasants (which we had in decent numbers up until about 2000). This little 5 lbs. 3 oz. gun took ruffed grouse in 6 states over one season.
Number two is my favorite quail gun: a Parker DHE 20 with 30 inch barrels. This little 1918 gun has proven a quail killer, and I've shot well with it. It will take a pheasant on those rare occasions that we find one, but it's a quail gun, pure and simple...and simply the "best."
Now, ask me again tomorrow...
