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From what I remember when I used to shoot handgun silhouette more than a few years ago, I don't think you can load a .357 Mag hot enough to reliably take rams at 200m in a T/C. I used a .357 Maximum, which worked fine. So, given your 3 options, go with the .44 Mag. I ended up switching from the .357 Max to a 7mm TC/U to get flatter trajectories.