[lentulusgracchus]

If you are going to bring in Barrett's offerings and the subject is penetration, have a look at his semiauto 4-round 25mm "payload" rifle, the XM109......it's the heaviest-caliber assault rifle I've ever heard of.

He also has a close-quarters battle, bobbed version of the M-107/M-82 .50-cal. rifle.

The drawback to a weapon like that in an urban scenario being that, if you miss, or even if you don't, there's a possibility that you accidentally bag Grandma four houses away.

Did someone say, "overpenetration"?

[burzum]

have a look at his semiauto 4-round 25mm "payload" rifle, the XM109......it's the heaviest-caliber assault rifle I've ever heard of.

Gotta post a picture:

Another drawback is that some people might confuse you with a tank if you carry this sniper rifle.

[GreenOgre]

It shoots through schools.