Help decide between 357 Supermag or 445 Supermag

[chazgin]

My favorite deer gun a 7 B***m barrel on a Contender went south today. The Contender is unlocking on every shot. I have a DW 357 Supermag 8" barrel with 2x Leupold and a 10" DW in 445 Supermag with same scope. Which should I use for mulies 0-150yds? The 357 with 180 Hornady HP/XTP or 445 with 240 or 300 HP/XTPs. Both revolvers shoot about the same. I only have 2 weeks left till early rifle opens here in Colorado. Any suggestions are welcome since I haven't shot any deer with these cartridges. Shot a lot of steel but not game.

[PaulS]

In my opinion 150 yards is beyond the envelope for the 357 "supermag" (AKA Maximum).
I have no data on the 445 Supermag but if your velocities are as high as or above the velocities of the 357 Maximum then it might work at 150 yards. That is if you can keep it on target at that range.
Out to 120 yards I would use the 357 Maximum with a 180 grain Hornady or Speer rifle bullet (mine is a TC Contender) seated in the cannelure which makes it too long for revolvers. With the long seating there is room for enough powder to get 1800-1900 FPS at the muzzle. Beyond 120 yards the velocity drops to the point where you just don't have sufficient power to kill cleanly (IMHO). I would bet that the same is true with the 445 Supermag.

[chazgin]

Pulled out the books and the 357 Supermag (Max) maxes out at about 1450 fps from a 10" Contender according to Lyman. This means less from a 8" revolver. About 630 ft lbs at 120 yds. That is right on the edge of acceptable. The 445 Supermag maxes out at 1600 fps for 1270 fps and 860 ft lbs with a 240 gr bullet at 100 yds. Certainly different then the 7 B***m which went 2450 fps with a 120 Nosler. Both revolvers can shoot well and a deer is bigger then the IMHSA turkey at 100 yds. I will limit shots to 100 yds or less from a field rest then, since shooting at real game is way different then shooting steel