American "Old" system:

12ga .729" bore

cyl=.000
skeet in=.005
i/c=.009
skeet out=.012
mod=.019
i/m=.025
full=.035

American "New" system

cyl=.000
sk in=.005
sk out=.008
i/c=.010
light mod=.015
mod=.020
i/mod=.025
light full=.030
full=.035
xtr/full=.040

I'd think the Brit system would imply 10, 20, 30, 40 pts but I could be, and probably am, wrong. I rely on Jim to tell me when I'm wrong and have never been disappointed. Incidentally, that first chart is the strait poop from "Mikey" Orlen.

jack