RE: Shotgun barrel length?
 

i dont think it realy would mater that much but for ducks geese turkey stay with long the other ones it shouldnt affect your shot that much you mihgt taking longer to swing at a phaesant quail or grouse but should be fine.

RE: Shotgun barrel length?
 

you pretty much hit the nail on the head with everything except the duck load, as an avid duck hunter I have always advised to use a size larger shot of steel than you would with lead. Personally I use 3"#4 steel with a mod choke propelled by a 28" Benelli M1 field. works for me!

RE: Shotgun barrel length?
 

speaking of long barrels I saw an ad for a barrel extension from hastings it screws into where you would put your choke tubes and it litterally doubles the length of your barrel !
Why in the world would anyone want almost 5 feet of barrel ?

RE: Shotgun barrel length?
 

Barrel length is a personal choice and can change from gun to gun , from o/u, auto ,pump. Shoot was fits and feels good in your hands, that pretty much sums up barrel length.
The length has absolutely nothing to do with how a shotgun will pattern. That will be determined by forcing cone, back boring (if any) and choke.
The only way to really decide whch choke/load is right in any particular shotgun is to spend some time patterning.