Excellent info, and solidifies what I've believed for decades. I have no loads beyond 1250 fps save one, and I tried that last night in 27 yard handicaps using my TM1 special w/extra full fixed choke. The load used was 1275 fps and gave me a little 'fringe' pattern that enabled a few extra hits when I was off a bit.
I've seen some guys bring loads that approach 1450 or so (turkey shoots) and they can't figure out why they're not breaking birds at 60 yards. I know their pattern's blown up but who am I to say anything?
At 16 yards my best load is 1 oz at 1150. It just smokes clays when I do my job.
Still, Neil you should take a break and have a brewski or two.. Even though I'm somewhat well versed in ballistics you've raised the bar a couple of feet.
Thanks for posting this info. Have a great weekend.