Bill,
I'm assuming the Winchester is a 12. Go buy some 1oz or 1 1/8 target loads in 7 1/2's. In the 20 use 7/8 or 1oz 7 1/2's. Most importantly- have a great time.

Having just shot a tower shoot, I can say that there is much good advice here. We used #8's and 7 1/2's target loads and cleaned up just fine. Perhaps larger shot might have brought some long shots but we went after the escapees with dogs later in the day and had fine time. David

Thanks David..
Did you shoot double gun ??

Bill, I shot two guns, a 12 ga Parker 1 1/2 frame D with F &F chokes and a 12 ga Parker G grade 2 frame with open chokes. Have fun! David