ok, now that we know what the heck you mean.....geez....
For me....Skeet, Sporting Clays and 5 Stand ....all have a lot of left and right movement to the targets...or dropping in from overhead, out of the brush, rising off the ground, etc...in sporting especially .....so I want the same gun for all 3 games... and for that,
...I want a well balanced gun at around 8.5 lbs..and in an O/U it would have 30" barrels - regardless of gague ( 12, 20, 28 or .410 )..../ and I would use the same guns for hunting live upland birds / especially if I'm in country that isn't too brushy...
If I want to shoot a lighter gun ....like 7.5 lbs...then I want a longer barrel ( like a 30" in a semi-auto ...to smooth out my swing and followthru. Benelli super sport is a light semi-auto ..and a 30" barrel there works for me.
I have a really hard time shoot real light and short guns - even if they fit me...I tend to "slap" at targets vs making a smooth shot.
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For Trap only.....I go to a 10lb gun and 32" barrels on an O/U....because even in Continental Trap there is less left to right bird movement / and its a single target.
If I were to shoot Bunker Trap...I'd go to my Skeet / Sporting gun over a "Trap gun".