Tinker,
Any speed indication that I would give you would be a pure guess on my part. I usually load these to about 1400 or so and because they are fairly aerodinamic for the short distance that I usually shoot them, I don't think they have shed too much of their speed, but I have no way to tell for sure. I have never had any of these fragment on our whitetails around here and have never found any lead slivers or anything like that in the deer carcases we cleaned. Because I have a bad leg, and because I don't get to still hunt as much as I used to like to do, most of my deer kills are made sitting next to a deer trail, out maybe 30 yards or so. Almost all shots are broadside, behind the shoulder. I have dropped several deer using a high shoulder shot, but never with this slug.
I am fairly sure they don't flatten as much as the one I showed that had gone through all the water jugs, and I would also guess from past recovered muzzleloader round balls, that they must surely hold together pretty well. The only slugs that I have seen that were greatly deformed were the ones that hit the spine or the shoulder joint. Even though they get twisted up some, most of them retained most of their original bullet weight. I am also fairly sure that the larger round balls that I used,(54,58,and 62 caliber), held together better than the 45 round balls do. It must have to do with the greater weight and mass. I used a .45 flintlock for years but have put it away. I now feel that it is really too small to be used on deer. It will kill them, but not in a fast, humane way. In our neighboring state of Missouri, they will let hunters use a .40 caliber round ball on deer. Both states should raise it up to .50 caliber, minimum, in my opinion. The 50 just kills so much better and in case of a bad shot, it at least leaves you a decent blood trail to follow. Bob