Took a little time from working on my farm machinery to do a little informal 480 work up. Chronograph stayed in the box and I have no sub MOA groups to show. Sunny and nearly 50 degrees with dwindling snow banks. Lets Shoot.
First load was a gallery type load. Sized a 50 cal. round ball to .476 tumble lubed the little footballs and put them over 5 gr of HS-6. More testing is required but.... Kind of a neet big chunk mouse fart load.
Second load was 10.5 gr HS-6 and the 400 lee sized .476 BAC lubed. May not be enough speed on this one to stabilize the 400.
Lastly I tested the 400 lee over 20 gr of AA #9. Should be just shy of 1300 fps. The load shows promise. Almost made the drill. 5 rounds 5 inch group in 5 seconds @ 25 yds. If you haven't tried the drill it's a hoot but only really fun with big guns.