RE: SHOOTING BIRDS AT 30+YRDS!!
The choke is the key. I have 2 different guns I use for turkeys.
#1 is a NEF handi rifle in a 12 guage 3.5 inch mag turkey barrel, with a extra full choke tube. I am shooting Remington 3.5 inch mag 5 shot out of this one. This one will shoot out to 60-70 yards and keep the bb's in a 8-10 inch circle at this range no problem but this one does kick like a mule and not reccomended for any small person.
#2is a Rem 870 20 guage with a super full undertaker choke tube 3 inch mag. Shooting Winchester 3 inch / size 5 shot shells. This will shoot out to 40-50 yards easily and pattern more than 10 bb's in a 8-10 inch circle at this range.
I have not had to run after a bird yet. Thay have all been pretty dead by the time I get them. If anything just break their neck when you get to them to make sure.
Just my 2 cents.