I was wrong on my shell they are 2 3/4 but I think I found the problem. I need to put a different shim in my gun to drop the barrel down. I've been shooting over the birds and I guess I get just enough of them to wound them. I'm going to change the shim and see if that helps but there are only four more days in the quail season here in OK so I may not get to see if it works this year but will be ready next year. Thanks again JW!