Hi Mark,,, wanted to welcome you to GTA.... nice to have you with us.
I don't own a Winchester 1100 and haven't had the opportunity to shoot one so I know nothing about the rifle but as for it's power..... that kind of power would work well with the heavier pellets. Try some of the heavier pellets and see how it shoots. That's the best way to take advantage of all that power.....
Again, welcome and I'll be looking forward to your future posts.....
Jeff