An officer on my PD had a holster-induced AD a few years ago with a G22. He was using a Shooting Systems holster (previously known by the less politically correct name "Assault Systems"). It is a thumb break style with a velcro adjustable strap for differing size semi-autos. That strap became a little sloppy with age and found its way into the trigger guard and if everything goes wrong when re-holstering the gun goes bang. Luckily, the officer was not injured. We were able to duplicate this, with an empty gun of course. A call was made to Shooting Systems who provided an upgrade strap that was reinforced to be more stiff and more difficult to accidentally find its way into the trigger guard. But the lesson is to pay attention to holster wear and chuck anything that compromises the trigger upon re-holstering.

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Tony