Will factory crimp type dies like sold by Lee work on lead or are they more for jacketed? I see Cowboy or Roll type dies advertised. Is this just a sales gimmick or really useful for lead which is all I use.
While I'm not a great fan of the Lee Factory Crimp Die, I do have three and they work very well on lead bullets.
Here is a report I did, with pics, of the Lee FCD for the .45 Colt.
There are several pics of different styles of lead bullets that shows just how it does work. http://forums.handloads.com/forum_posts.asp?TID=9905&KW=J+Miller
Almost all but a few of my reloads are with hard cast bullets. I use the FCD on all of my .45ACP rds. Seems to feed much better when using certain bullets and some batches of mixed brass. I use it sometimes with .357, 44 mag and .45 Colt loads. Never felt the need for it with 9MM or .38sp loads.
I'll jump on the "don't waste your time and money" bandwagon. FCDs do work but so do other brands of crimp dies. The secret in any crimp die is getting them adjusted properly. The real proof is on the target, over a chronograph, and cycling in the gun.
My Dillon crimp dies do a great job crimping what ever I load. They function flawless, group tight, and have very tight max velocity spreads.
A few years ago, I bought FCDs in 38/357, 45 ACP, 45 Colt, and 44 Mag. I tested the loads over a chronograph and on paper then compared them with my Dillon crimps. FCDs didn't fare as well as my Dillon crimp dies, especially when it came to max velocity spreads.