Trim die also form die?

[Hinnerk]

Am I correct to think that an RCBS trim die also functions as a form die or do I need to form my brass separately before trimming them in the trim die? This is the kind of trim die where you saw off and/or file off the brass that sticks out the top when it is run up through the die in the press.

[Pardini]

The form die can be used to trim in some cases.