[Mirikon]

I could see a troll sniper firing a 20mm Lottie...

[Angelone]

In Shadowrun you can always get a new collorbone. Hell you could probably get a bulk discount.

[DoubleTap]

the isrealies, and I think south africa, has 20mm anti armor rifles, sans broken collar bones.  Besides think about ww2 relic of a anti armor rifle, + bone lacing equals anti persuit sniper. 

[Mach]

The NYPD have an anti-tank rifle for shooting down planes that have been hijacked by terrorists. While i'm not entirely certain it will help should the need arise, its nice to know somebody actually thought of it.

[Deliverator]

Barret made something called the M109, it is a 20mm anti-material rifle. Though it is a short barreled (relatively) rifle so it is not particularly accurate.  20mm rounds aren't particularly accurate anyway. Even the .50 BMG is not a particularly accurate cartridge which is why people came up with things like the .416 cartridge which has almost identical terminal ballistics but is more accurate at the longest ranges.

[CanRay]

Yeah, it's too bad that you can't hit something a FEW KLICKS AWAY with a .50 BMG.