In the situation you described I see no reason to go buy a .45. First, you're talking about selling a good amount of ammo just to be able to make the purchase, ammo that could be used for training with the 9mm. Second, you've stated that you are already familiar with shooting 9mm...I presume with accuracy. Why switch to another caliber for a "perceived" improvement that many (including me) believe is a fallacy? You never mentioned what 9mm firearm you have. That could factor in too.

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