With all the craze in the Midwestern states regarding straight wall cartridges, HausofArms has partnered with MGM (Match Grade Machine) in Utah and has done a special batch of these barrels to fill that need. These are TC G2 Contender Stainless Steel barrels 20" BULL contour (any factory G2 rifle forend will work) chambered in 357 REM MAX with a 1 in 16" twist and 5R rifling. THEY ARE THREADED 5/8-24 WITH A CAP. These barrels will fit any TC Contender as well as fit any factory rifle forend.
Dylan at MGM had some velocity testing on these calibers by an independent 3rd party, check out this link it is extremely informative and will answer alot of your questions regarding barrel length and velocity.