RE: 20 guage mossberg
My sone has the same gun. I think my sons load is a Remington Nitro 3" #4 or #5, not sure on the shot size. Patterns real well at 30-35 yrds. That was with the full choke too. He is 10 and only about 60lbs. He can take a few shots but likes the3" steel for duck better. LOL
These loads will not kill the pockett either.... They actualy patterned better than my 12.