The magazine exploded about 9 p.m. ET, spraying casing fragments at high speed and striking Walker. She managed to pick some of the fragments out of her leg and chest and then took a bus to the hospital, where she was treated and released.

Sandy told police he'd stored the gun in a drawer but had stored the magazine in the oven. Four rounds were in the 13-capacity magazine, he said.

Gun and ammunition references indicate that the .45-caliber bullets commonly used in Glocks can explode at temperatures as low as 280 degrees — or even lower if they've been exposed to heat for a long time, which can degrades the structure. 

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