Tom:
I load 7/8 oz (same wad as above) with 18 grns of PB or 14 grns of Clays. These are about 7500 psi and shoot well. I joined the 16GA society and got their extensive list of good 16ga loads. You might like to check them out at
www.16ga.com (click on the picture) I also have shot 2 1/2" shells from Polywad, WM. Larkin Moore, and find these low pressure loads shoot well in my old British doubles, including the Damascus guns.