You will be surprised when you open up an Xpert shell and look at what's inside.

Anywho, like CJ said, steel is 'light.' The density is so poor that steel shot can not hold its velocity very long. The only way to overcome this is to go bigger (weight increases faster than cross-sectional surface area in a sphere, so therefore ballistic coefficient improves as the sphere gets larger). Be mindful not to be taking very long shots. If you need to shoot further, you need to shoot bigger. It may help to shoot a more premium shell; bigger shot like BBs will be pretty decent in cheap shells but 4s are going to look like pears. I usually shoot nothing but 3s for all my duck hunting, and xperts suffice, because I shoot fairly close up 10-30yds. One thing you need to do is get some big paper and shoot it to see how your patterns are looking. You may need to switch chokes, ammo, or both if you have ugly spotty patterns.