Trent Crump said 10 to 15 percent of the department's 3, 000 officers, who are assigned .40-caliber and .45-caliber handguns, had taken advantage of the ammunition for practice shooting.

WSJ: Laws, rumors have ammo flying off store shelves

In Phoenix, the Police Department has stopped providing officers with 100 rounds of ammunition per month for practice.

WSJ: Laws, rumors have ammo flying off store shelves

Former crew members say that, in practice, the guns are never fired simultaneously, partly because of ammunition considerations.

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