The time for my annual LEOSA requalification had rolled around again, so I brought my S&W revolver and Kimber .45 over to Greybeard's Denton County Sports Association range in Argyle to take care of that chore.
I usually qualify with the 4" Kimber Pro Carry that is my most frequent EDC, but I had just changed the recoil spring and hadn't tested it yet, and it's my practice not to use a gun I've modified for either carry or qualification until I have verified proper function with a couple of boxes of ammo.
I know changing one Kimber original spring for another of the same specs shouldn't affect anything, but I'm not one to take such things for granted, so I brought along a 5" Kimber to maintain the same operational parameters during the qualification run. I hadn't made any changes to that gun other than swapping out the hard grips for a nice comfortable set of Hogue wraparound rubber grips with finger grooves that felt really good in the hand. I had only shot it once or twice since then, but figured I was good to go because I hadn't changed anything that could affect operation. That turned out to be an unwarranted assumption.
Greybeard gave me the signal for the first shot on the first target with the .45. When I pressed the trigger it didn't move and the hammer didn't fall.
Not good.
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A quick check showed the slide was in battery, the thumb safety was off (I rest my strong hand thumb on it during shooting to make sure it stays that way), and the grip safety appeared to be depressed.
While I was puzzling over the cause, Greybeard dutifully confiscated one of my remaining rounds to make sure I didn't squeak in a shot I wasn't entitled to somewhere, guaranteeing the only point I've lost in a qualification in years.
I checked the gun over and couldn't find anything wrong with it, and finished the qualification with no further issues. I then ran a bunch of mixed ammo through the Pro Carry to test the recoil spring, and it worked just fine.
The incident bugged me that night and all the next day, and by the time I went to clean the guns about 24 hours later I had determined that grip safety operation was the most likely culprit. Again, I couldn't find any mechanical issue with it. I compared its operation to the function of the one on the 4" gun which was equipped with a thin set of wraparound Crimson Trace Lasergrips, and they appeared identical. Then I tried picking up each unloaded gun alternately a few times and dry firing.
Sure enough, after a few tries, I duplicated the issue on the 5". I didn't move anything and examined everything as it was right then. The grip safety appeared to be depressed, but by some infinitesimal fraction of an inch it wasn't down far enough to fully clear the movement of the trigger bar. Why? Because the extra thick rubber grips and thick finger grooves on the front strap had opened up the way my hand grips the gun just enough to make proper operation of the grip safety unreliable.
When I carefully adjusted my grip to make the grip safety work, I discovered that when the grip safety was depressed enough to allow the gun to fire, it wasn't down the full distance of its travel and there was no margin for error at all. The size and shape of the grips combined with the size and shape of my hand was simply a bad combination.
To verify that was the problem, I swapped out the finger groove grips for a flat set of hard rubber ones and did the alternating gun dry fire exercise again. Using repeated hasty grips, I couldn't get the problem to recur.
Lesson learned:
Do repeated dry fire and range testing after any change to a gun before trusting it for carry or qualification, even if you can't see any way that it could affect operation.
Although this experience irked me no end because of the lost point (I'm a perfectionist), I was very happy it had occurred where it did.
Failure to get off a shot you intend to fire is
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That sure beats
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