H2O,
I've only had the Max barrel for about 5 months now. (In it's Max configuration that is)
I had Mike Bellm rechamber it from a 357 Mag. with what is called the "Alternate" throat. Pretty much what is referred to as a tapered ball seat type.
I had always wanted to try an efficient round for the 10" barrel with some horsepower in 35 caliber. The 357 Herrett is an efficient round also in the 10" bbl. however, you get into case forming. I see this round in a 12" bbl though ultimately.
General impressions of the Max in the Contender are it is very controllable without a Brake, achieves excellent velocity for the 10" barrel length, (1850-1900 with a cast 180) is easy to work with the cases, easy to load for as to not being finicky, is wonderfully accurate (so far about 1" at 50 yds), and makes the Contender into a compact powerhouse suitable for Deer out to say 150 yds or less. Some would say more, some would say less.
No super duper scope mounts are needed although I highly recommend the Leupold or Burris double dovetail base and Burris Signature rings. These hold real well.
Standard 357 Mag carbide dies can be used to load this round.
You can use 38 special, 360 DW, 357 Mag and of course 357 Max brass in it. Case thrust on the standing breech is considerably less than the larger diameter cases too. This is a 48,000 CUP cartridge.
The most useful bullet weight perhaps is the 180 gr with the 200 close second.
With the proper throat arrangement, like my barrel has, you can go up to 220 gr bullets depending on their design. It's a cast bullet friendly cartridge in my experience and that of countless others to be sure.
I'd go with the 10" length or perhaps a 12" but no more as it loses it's compactness and if you are going longer, might as well chamber for something more powerful to take advantage of the barrel length in my opinion.
This round is pretty much a handloaders proposition now but Remington brass is still available at a reasonable price. It will last fairly long as it is a straightwalled case if not abused. A 38 super carbide die can be used to not overly work the brass and then a 357 mag carbide sizer can be used to "neck" size after that. That's a tip from the Steel shooting boys.
To me, it is an extremely cost effective conversion to make on a factory 357 Mag barrel with a toilet bowl throat. Obtain a 357 Mag bbl. at a very reasonable cost, mine was used, have it rechambered to Max with a quality throat, and perhaps a look at the crown and you are ready to go rather cheaply as barrel costs go.
Some have great luck with the factory Mag or Max barrels with their very long forcing cone throats. I never did and went with the conversion.
All in all, this is a real sleeper round that was killed off prematurely over a non-issue as it is a lot of fun to shoot and entirely suitable for deer, hogs, black bear and such at reasonable ranges.
I'm currently experimenting with Surplus WC680 powder and there is a thread down below this one I think about that. Suitable powders run the gamut from IMR 4227, 296/H110, AA1680, WW680, WC680 Surplus, WC820 Surplus.
The bullet situation can be tricky as far as performance on game. For Jacketed, I'm inclined to go with the Hornady XTP 180 (Dual Crimp Groove) and 158 gr XTP Flat Point (will take the higher velocities). Nosler partition hangun bullets have been also recommended to me. The Hornady 180 SSSP or Speer 180 FP may or may not expand for you depending on the range/speed at impact. Cast may prove to be the ultimate bullet for this cartridge. Currently working with the Beartooth 180 WLN+P.
Again some of this info is subjective opinion but on the whole, I hope it helps you in your quest.
Regards