My second ever Contender barrel was a 10" 30Herrett, in 1974, I think. When I realized what the round could and would do I thought I'd arrived at the pearly gates....WOW. Now almost forty years later, I still enjoy it and currently own 3 barrels chambered for it. I would offer that I learned more about reloading, head spacing, brass forming and etc. from the Herrett than any other cartridge and maybe all the rest combined. At times it was a little frustrating and challenging, but it was all worth it. Back when bullet selection was nothing like today, I used little else than 100-110gr pills and still, almost never shoot anything over 130gr. WW680 was absolutely THE stuff...when it was discontinued I hoarded all I could get my hands on and even still have a little left.
The tip I'll pass on is, if you can find or have a 30Lugar (I think a 30Mauser is almost the same and may work too) sizing die, use it to push the shoulder back instead of the Herrett die. It is has a more tapered shoulder than the sharp shouldered Herrett and is much easier on brass.
Anything you can find written by Bob Milek about the Herrett you can trust. He and Steve Herrett thought up the whole deal and talked TC into making it. Thank You...Bob and Steve! Enjoy my friend...it's a great venture.
Walt