Range of your .410 pattern? Choke for your gun you are testing.
Years ago, when I was shooting a lot of Skeet with a .410 to cure a flinch, I had a set of tubes made by Briley. In them I had choke tubes made with .002 increasing amounts of chokes from true cylinder up to .026 constriction. Nothing much above .020 pattern well with what loads I was reloading at the time or factory shells for that matter. With factory Remington shells .012 and .016 was real good for doubles. Anything from .008 to .016 worked well for Skeet. For 16 yard trap I found .016 to .020 worked well but saw no advantage much above .020. With 300MP I bet that my results would be even better. Back then we had 2400, 296/H110 and IMR4227 as our basic powders.
Are true nickel plated 8's that much harder than high quality magnum shot? And do they weigh less? Does it take more room to get a full 3/4 ounce in shell? You are starting a very interesting project I think.
