You will not lose an arm if shot by a .357....
Actually, you might.
I won't say its likely, but it is possible.
It will not drop a man with one shot, and will not crack the engine block of a Chevy.
The one person I have seen shot with a .357 stayed on his feet for approximately 30 seconds, and then fell. He was hit in the shin!
I don't know about cracking the engine block of a Chevy, but I do know the .357 will absolutely shatter 17cm of bone, and I have (somewhere) the X-rays to prove it! No piece of the bone was larger than 1/4" to 3/8" along the bullet path.
According to the doctors, if the bullet had hit as little as 1/4" away from where it did they would have been forced to amputate.
Lose the limb from a .357 Mag hit? it could happen
And FYI, the hit I'm talking about was a 160gr SWC driven by a case full of H110. Unsure if a 125gr JHP in the same spot and angle would have been "better" or "worse".