OT/OT Clip vs. Magazine - What's the difference

I was corrected yesterday by one of the federal marshalls who guard
this federal bldg where I slave away at my institutional beige
desk.....

what is the difference btwn a clip and a magazine? I was referring to
that clip on CNN of an officer being shot as he turned his back on
someone he stopped. I said he emptied his clip, he said it was a
magazine....

thx all - Craig

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