Are you doing lots of shooting, seeing lots, or seeing lots and not getting them close enough? Im not sure where to start. Lets assume you are shooting lots and not getting a whole lot. What I use for starters, (and alot of other people will vary, you have to find out what patterns best and works best for you, and yes sometimes the hard way.) I will use for ducks, either 1 1/4 ounce or 1 1/8 ounce number 2's in steel. 3 inch, or 3 1/2 inch, whatever you have. I usually stick with the fastest stuff you can get. Try the Winchester expert hi velocity, or the Kent fast steel stuff, but again stick with the fast stuff, better cuz less lead is needed. Use either modified or improved cylinder choke, I prefer the imp. cyl. I like to keep my shot open. And as for barrel length, shouldnt really much matter, I suppose the typical 26, 28, or even the 30 inch barrel is fine. I have a 26 incher on mine. Any other questions, as lots of people are glad to help!!