Try a Glock 18 with an extended 31 round magazine and three shot burst fire option. fires at 1200 RPM. Used by law enforcement and the military. If you feeling juicy the standard models can use the .45 rounds. They're also fairly easy to fit into any RP as they're fairly easy to get ahold of (Apart from the 18 unless your playing a soldier of securty agent of some kind).

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Inquisitor Lord Fyodor Karamazov
"There is no such thing as a plea of innocence in my court. A plea of innocence is guilty of wasting my time. Guilty!"