SBE is Super Black Eagle (Benelli)

Thanks for educating me. Benelli sure make some fine shotguns.

As mentioned, regardless of gauge the pellets will hit with the same power if going the same velocity, but pattern is the key. I killed several turkeys with a 20 before I could take a 12, and my brother did also. He shot one the farthest, about 32 steps, and it dropped immediately, but flopped around immediately and for a few minutes like it just wasn't quite nailed enough. We used both 3" 5's and 6's. I think 4's are restricting your pattern a bit much, as you are already restricted by going with a 20.

We used Rem 870 youth guns with standard full choke.

dawei,

Benelli Super Black Eagle. oops! put this in before I knew about snowdog2's post.

My wife uses a 20 with #6 hevi shot and it does great out to 35 with a standard full choke.

What make, model of 20GA does she use? Also are you using 1¼ or 1 1/8oz loads?

WELP ADVICE CAN ONLY TAKE YOU SO FAR. My suggestion is to get out there and pattern your gun yourself and find out the hard way. The proof is in the pudding, so get out there and try some different shot and get the best one for you.