I wanted to make sure I had my facts straight before I posted on this subject again, so I called Lyman, Hornady, Lee, and RCBS today to ask about their 45 ACP dies. Lyman and Hornady both said that the crimp in their seating die is a roll crimp, and if you want a taper crimp you have to use a separate taper crimp die. Lee says there seating die is a "modified taper crimp" die which can give you either a roll or a taper depending on how deep you set the die. ( I used to use Lee dies, and in my book, its a roll crimp.) RCBS says they changed about 17 years ago to a taper crimp in their seating die. They used to have a roll crimp in their seating die. The "newer" dies with the taper crimp are marked TC Seating. At this point I do everything on Star reloaders and the Star Seating die has a roll crimp.
It has been my experience that if its a true taper crimp die, it doesn't matter how much you crimp the case, it will still look like a taper crimp. If you crimp it and it looks like a roll crimp, its a roll crimp. You know, if quacks like a duck ....... If you don't flair your cased too much, you can use a roll crimp die to carefully remove the flair to the point that the case wall is almost straight, but IMO that's not the same thing as a taper crimp.
I reload and shoot 15,000 - 20,000 rounds for 45 ACP each year.