Yes, I use them. I don't know how they work in your Dillon 650 though. I use a Lee press. I'm sure someone else will be able to answer you though.
the Factory Crimp page-The die comes both ways, taper and roll.
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Lee Carbide Factory Crimp Die
For Handgun Ammunition That Must Work
A carbide sizes the cartridge while it is being crimped so every round will positively chamber freely with factory like dependability.
The adjusting screw quickly and easily sets the desired amount of crimp. It is impossible to buckle the case as with a conventional seating die. Trim length is not critical so this extra operation takes less time than it would if cases were trimmed and chamfered.
Revolver dies roll crimp with no limit as to the amount. A perfect taper crimp is applied to auto-loader rounds. The crimper cannot be misadjusted to make a case mouth too small to properly head-space. A firm crimp is essential for dependable and accurate ammunition. It will eliminate the problems of poor ignition of slow burning magnum powders.[/quote]