I'm suprised I haven't seen this site referenced more here.
While I usually hate linking to other forums some of this guys stuff is absolutely insane.
Guy who runs this site is named Robert Silvers. Who also has a bunker on his property with 2-3 of every modern firearm made. He is involved with AAC Advanced Armament Corp http://www.advanced-armament.com
and the manufacturing of silencers.
The AAC Silencer shoot is pretty cool. Not sure wassup with the M79 though ;P More quiet then firing a bunch of airsoft guns. The last guy with the Barrett HAHAHA.
If you follow airsoft news you'l see that AAC has licensed with Private Parts Airsoft to make airsoft versions of their silencers.