Fourdogs:
Sometimes numbers can be misleading. For instance I shot a few Buffalo Bore 340gr +P+ 1425fps/1533 ft.lbs from my 4 3/4" FA at a large stainless steel plate that was maybe 3/16 thick from about 10 yards. Those are some serious rounds. When one of those lit off I got moved back about a step. They put a serious dent in that plate. Nothing remained but splatter.
Next up was my 7 1/2" FA 454 with a Colt cylinder. It was ported ( later had the barrel cut down to 5 1/2" ) so I figured I was losing some velocity which made it a fairly even match with my 44 barrel. I made up some 360gr wheel weight boolits with 16 grains of 4227 which most of you know is a pretty tame load. The gun hardly moved because of the ports, but the dents in the plate were huge, much deeper and wider than the 44.
I'm guessing the BB was moving so fast it disintrigrated which it did. The 360's were moving maybe 1100 ( just a guess ) but they had more authority and actually blew the plate off the stand whereas the BB didn't move the plate at all. Wish I still had that plate. It would be instructive to post a pic.
This wasn't very scientific but it was enough to finally give the nod to the 454 and I sold the 44.
Fourdogs, that is a pretty nifty little test. However, I doubt that the 44 load was traveling at rated velocity from your 4.75 inch barrel. A near 3 inch difference between both guns is a huge difference in velocity and give equal barrel lengths the results might have been closer. However, the 454 average loads are equal to the BB44 load(which is the max 44 mag load) and with the 454 you can go to levels the 44 will never attain. Also, interesting that the BB bullet disintegrated. I would have expected more toughness out of it.