Crimp will be needed with some powders, especially H110, 296 or some of the other powders, if you don't crimp you will get wide velocity variations...don't know why, but your chrono will tell you if your groups don't.
As for 357 max, my TC barrel is .356 (a Bellm rechamber of a mag) and my VVCG is .357 I think the max is the best ten inch barrel for your contender bar none. The 180 grain hornady SSP is hard to beat but the 180 remington semi-jackets are also good. Good luck with the Max.
regards,
Graycg