There is no difference when shooting them at some attacking you with a knife. As stated by OKFCO5 calculated recoil and felt recoil are 2 different animals. After you put 50 rds through the gun, I believe I could load 165/180 in a mag and you would not "KNOW" which was which. You may have a sense one was louder, heavier etc, but you would be guessing. I have shot thousands of 40 since early 1990's and I doubt that I could tell you which was which in a quick string of fire, possibly , if I was fresh , just starting, and took 10-15 min per round to analyze it , I may see trends, but not a significant difference. try both than interchange them and see if one is "unpleasant" compared to the other. I carry Winchester 165 ranger. Be Safe,

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I BACK OUR BLUE