You can purchase factory formed Federal brass (Nickel plated) from Beikirch Ammunition Company. They are located at P.O. Box 151, 930 Linden Avenue, East Rochester NY. 14445-0151. Phones are 800-622-3006 (orders only), 585-248-3660 or 248-3434. Fax is 585-248-3973. Last time I bought was about a year ago and I believe the cost was about $35.00 for 100 rounds.
I prefer to go this route for a few reasons. First the Federal cases are headstamped 7X30 Waters, which helps prevent ammunition mix ups. Second is the fact that you will "waste" a box bullets plus the primers and powder required to fireform 30-30 brass. I'm estimating this cost at about $14.00 for 100 rounds. Of course, I never really consider any chance to get out and shoot, a "waste" of ammunition.
The only downside is the fact that the cases are nickel plated. Some people don't like nickel brass, as they believe it is harder due to the plating process. I just like getting brass that is ready to go. But that's just my two cents.