Raising the minimum age to purchase an AR-15, as Democrats and some Republicans want to do, will do nothing but inconvenience lawful gun owners. According to information collected by Everytown for Gun Safety, Since 2009 there have been 156 mass shooting incidents — defined as four or more people shot and killed, not including the shooter. Eleven mass shootings have been committed by men 21 and younger, and two of those (or 1.3 percent of the total) were committed using an assault rifle. Meanwhile, only one of those rifles were purchased legally.