I think the best description I have found on forming cases was in a Nosler manual.
The down and dirty is, simply start with your die set up a bit high, and turn it down about an 8th turn at a time until you can close the action with a little felt pressure. What this does is put a false shoulder on the case. This holds it in place in the chamber so that it will not move forward when fired. Pick a medium burn rate powder for the bullet you intend to use for forming,( the cheapest you can find preferably), load them up and go have fun.
Some folks recommend seating the bullets out to the lands, which in some cases is fine, but with the Contender frame your not working with the strength of a bolt action rifle. It doesn't take much and your into pressure areas you don't want to be. Others might recommend using cream of wheat as well, but I tried it once and to be quite honest, I wasn't impressed with it or the mess. Your mileage may vary though.
With the first mentioned process, I have formed over 500 cases and not lost any, and the standard Winchester cases last seemingly forever, and are cheap and usually readily available. They all fully formed on the first go round. I used some bulk 150gr bullets I got from a gunshow for cheap, and some Accurate. Like I said I went the cheap route but FF the loads shot easily MOA at 100yds.
For my final loads, I went with the 139 - 140gr bullets over the more common 120 gr loads most seem to like. I wanted the most I could get from my loads with regards to down range energy. My initial goal was a 200 yard hunting load which came about with the 140gr Nosler Ballistic Tip, or Hornady 139gr BTSP or SST, Winchester cases, CCI-BR2 primers and RL-15. The final load is pretty boring to shoot at 100yards as it just seemingly enlarges the initial hole. I used it on a decent whitetail doe at 282 yards and it was a bang flop deal.
The key thing I can recommend is contacting the manufacturer of what ever bullet you have in mind, and asking them about the minimum velocity required for at least double caliber expansion. This will give you a REAL idea of your loads and the limitations you need to consider when working them up. Your only going to get around 2250 or so at max for a safe top end velocity from the 14" barrel. Don't get me wrong, the 7x30 is an awesome caliber for handgun hunting, and with todays wide selection of bullets and styles there are a lot of options. IMO the better ones are Berger, Nosler, and Hornady which all have known accuracy, and rapid expanding bullets. This will not only let you workup a very reliable load, but also extend your ranges to your maximum potential. Even if you do not hunt with it over 100yds, it's great fun and practice to shoot out at 2-300yards so you know what it will do should a yote or hog roll out on you.
Hope this helps.
