I've been roll crimping all of my steel shot loads now, and I can tell you this... the roll crimper from precision reloading is vastly superior to the BP one that I have. I have sero problems even rolling old fold crimps. They start out a tad ugly, but just tun into beautifull roll crimps in a matter of seconds. I still use the BP one in 410, and have found that you will do best by cutting off the old fold crimp... or ordering the new fiocci hulls, and using a counter clockwise slow rotation. In fat, they look and shoot better than facotry.
Like i said, I made my sizer out of a lee decapper base,( couple of bucks), and just drilled out the hile that was already centered there. I ordered 2 so I could enlarge the second base to allow decapping the 209 primers easier. This took all of a few minutes. For removing my resizer, I just use a small piece f 1/2" metal conduit that I had laying around. I set the sizer on top and just tap the shell out with my dowel until it is loose and then remove the sizer.
I looked at using a Mec and settled on this method. I rarely use my Mec of Lee anymore for even loading 1 ga, as I am roll crimping and do most of the operations, except resizing and de-capping, by hand, including adding powder and seating the wad and shot.
I have the bass shotshell and prefer this method better, as well as the final product. I personally have settled on the BP stretch wad and something like 18 gr of H110 in a fiocci 2 1/2 oz load. I would have to look through my data to get the charge if you need it. BP goes all of th way up the like 20 gr, but again, i would have to look it up. They do have that data on thier web site.
I made my own hull vise out of a couple of peices of wood with a couple of bolts and wing nuts. I bored it out to hold 12 ga and 410. I stole the idea off line by googling homemade shotshell vise, or something like that.
Let us know how this turns out for you!