Wade, have you tried the 9mm in the big bore bowling pin events?
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The advantage of the 9mm is greater mag capacity, easier to shoot and get back on target and most times they are more accurate. What's your experience on this?
I have not shot the 9mm in large bore events. I have seen guys use 9mm's and I think what I have seen mostly mirrors your experience. On fresh pins, the 9mm is enough to get the job done, and the shooter gets the advantages you've identified. However, as pins gain weight, the 9mm isn't enough. As others have said, momentum is key in a bowling pin match, and the 9mm just can't produce the necessary momentum, even with a 147gr bullet. (At our club, there is no "capacity advantage" with the 9mm, as our rules limit all guns to 6 rounds per magazine.)
As an aside, I've seen guys shoot 185gr bullets out of the .45 ACP in an attempt to lesson recoil, yet still have enough momentum. It didn't work though, because the lighter bullets didn't move pins when they got heavy. So the guys loaded the 185gr bullets to really hot sppeds (1000 fps, 1050 fps, or even a smidge faster). That, of course, increased the recoil and still only got them momentum numbers that were about equal to a 230gr bullet at 850 fps.
And just to be clear, I'm just answering a bowling pin question--I'm in no way saying that any of this has any impact on the question of what's best for self-defense.
