Nice catch with just the right amount of character.
The 41 mags in a 57 or 58 were popular with the Detroit officers when I was there in the 70's and Remington had the 210 lead SWC. We could not carry a jacketed round.
Back then you could shoot a fleeing felon and I saw a B&E man that took a round right to the back of his head as he fled the scene. Needless to say, he never stole again. Ah, the good old days.