Would you rather have 15 round of 9mm, or 8 rounds of 45 in yor carry gun
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I am curious to see if folks are drifting away from the 45 due to the cost of practice ammo.
Simple answer? I'd carry either an 8-rd capacity 9mm or 8-rd capacity .45 and feel fine with either. Which is lighter and/or smaller? I've done my time having to carry full-size duty weapons 8-18 hours every day.
My personally-owned 9's have mag capacities of 7, 8 & 10-rds.
My .45's have mag capacities of 6, 7, 8 & 10-rds.
As a daily weapon for my retirement CCW needs? Mostly depends on my planned activities, clothing choices and how large/heavy of a pistol I feel like carrying.
Now, if I were going to return to active/uniformed duty? I'd opt for whichever hi-cap 9mm was available for issue. FWIW, I've carried issued 9, .40 & .45 on-duty over the years, and I really don't have a preference one way or another when it comes to caliber considerations anymore.
If I'm going to be required to carry a larger duty pistol? I might as well go for the higher capacity mag model, if available. And/or the lighter one, too, if possible. (I'd no longer care to use a personally-owned weapon that might be taken into property after a shooting incident, or could end up being damaged during duty usage. If something were to happen to my primary weapon, I'd rather be using the agency weapon and have them hand me another one that looked just like the first one.
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For some marginally skilled shooters? The reduced recoil of the 9mm might offer an advantage when it comes to recoil management, controllability, both of which can have an influence on being able to shoot accurately. It's certainly not a surprise that a lot of folks find it easier to shoot 9's than .40's or even .45's.
For the folks who think (hope) sheer mag capacity might help offset lack of training, skill and experience? It's probably not unfair to give some thought to the old saying that often goes along the line of that you can't miss fast enough (or miss with enough rounds) to 'win'.
Of course, I'm also someone who often carries one of my assorted J-frame 5-shot snubs, instead of any of my pistols, most of the time.