Neutron:
I'm a real fan of the Max in a 14 inch barrel and can attest to the fact that it is an excellant deer cartridge. I think that you are lucky in finding a 24 inch barrel I have not seen one that was reasonable priced and I have been looking.
As to loading. I bought a 1000 cases from Midway maybe 10 years ago and I understand they still have them. I use regular .357 Mag dies in a single stage press. I used a near full case of AA 1680 for powder but switched over to military surplus WC 680 and could tell no difference in accuracy (my barrel is not super accurate, just good enough to kill deer). I buy 180 gr Reminton JHP in bulk at Midway and they have killed a fair share of deer but in the pass few years I have been hunting with the Hornady 180 gr SSP. It has a better BC and I needed it this year (I killed a 120 class buck at 30 feet) bullet took out the shoulder joint and the top of both lungs, it did not exit.
Getting 1800+ feet per sec is not real difficult in the 14 inch barrel. Small rifle primers are a must for the pressure you are generating, I use winchester primers. In a 24 inch barrel you should crack 2000 feet per second with a 180 grain bullet with out trying. I tried lil gun but did not have a lot of time to play with it and may want to go back to it this summer when I have the time.