The 500 Smith would be too big and unwieldy for me, I practice shooting weak side and one handed in the event my strong side or, one hand/arm was injured.
A good S&W 629 DA revolver with a 4 or 5 inch barrel firing 240 gr XTP's at an easily controlled 1200 fps or so would be my choice.
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I would not personally pick XTP over a hard cast due to penetration issues. Just me personally.
Like XTPs on deer though. Very much.