1) Accidentally or even maliciously urinating on a toilet seat (preferably not belonging to the urinator) so as to make the janitor or house owner clean it up

2) A type of bullet cartridge that instead of having the primer cap in the very center of the shell has it along the edge. Most common in .22 practice or hunting ammo.
1)

Tim-Want to go drinking later?

Steve the Busboy-I can't. Someone pulled a rimfire and an upper decker in the bathroom and I gotta clean it.

2)
Bob-What type of gun you practice with?

Ken-I got a Remington 66 .22 long rimfire

Bob-Pfff that caliber is for pussies

Ken-Don't be a dick
by GrizzlyBearone September 6, 2011
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The painful, burning rash one experiences the day after an intense 'salad-tossing'.
Guy 1: "Hey dude did you get with Christine last night?"
Guy 2: "Yeah man, I got some nasty rimfire up in here!"
by Stinky Pinky88 May 6, 2009
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