Dude..Nearly 10,000 Americans die every year from gunshots. excluding suicide and you pull out one or two examples of a an armed citizen intervening? 

Silencer, suppression device, wrap a towel around barrel with duct tape...Who cares. Wear better ear protection for goodness sakes. Same with large magazines....Over kill, if you will excuse the pun.

The "gun free" festival zone was small. Across the street from the concert it was legal to carry so their must have been a couple ammo-sexual bumbling around. Heck you can walk right off the strip and fire a real machine gun for a $100.

Our guns laws are full of holes just like the  victims in Vegas and other gun massacres in America and fully blame the NRA.