Most everyone's standard pistol seating die will crimp if you run the bullet in there far enough. Problem is that as the crimp is being applied, the bullet is still being seated. This will shave a little lead forward of the case mouth and, although it may not give you a problem in standard field grade guns; it can be problematic in a match barrel with the headspace set close to minimum.

I had this discussion with Paul Miller of Colorado Cast Bullets about 20 years ago when I first started competing in IPSC. Why do I need a separate taper crimp die? My regular seating die works just fine. It turned out he was right; and I also discovered that the taper crimped rounds group a little better, have a narrower SD of velocity, and are less critical to case length consistency. Better mousetrap.