Lopez bought the gun from the same store as Hasan
http://www.latimes.com/nation/nationnow/la-na-nn-fort-hood-shooting-20140403,0,864732.story
Army Spec. Ivan Lopez who opened fire at Ft. Hood on Wednesday, killing three and wounding 16 before killing himself bought his weapon at the same store that supplied both Maj. Nidal Malik Hasan for his deadly rampage in 2009 and an Army private for a failed plot to execute a similar massacre in 2011, according to two federal law enforcement sources.
Hasan killed 13 people and wounded more than 30 using a pistol from the Guns Galore store in Killeen. It was the deadliest military base shooting in U.S. history. Two years later an AWOL Army private from Kentucky, Naser Jason Abdo, entered the same store and bought gunpowder, shotgun shells and a handgun. In that instance the store notified authorities, who arrested Abdo at a nearby motel where he was plotting to attack a restaurant popular with Ft. Hood personnel.
An employee at Guns Galore said that the owners wife had talked to the FBI. An employee reached by phone declined to say whether store workers noticed anything of concern about Lopez, who legally purchased a semi-automatic .45-caliber Smith & Wesson pistol. Its an ongoing investigation. We have been told to redirect everybody to the FBI, the employee said.
Military officials were scouring Lopez's background. He saw no combat during his 2011 service in Iraq and was not wounded, Secretary of the Army John McHugh told the Senate Armed Services Committee on Thursday morning
As I keep saying, we actually do know who a lot of the bad actors here are, and we could actually act on it if the GOP would stop hobbling ATF. There are a relatively small set of gunmakers and gun dealers who sell a disproportionate amount of the guns that are used in homicides (this doesn't seem to correlate with the much larger number of suicides, but it's something). We shut down the "ring of fire" back in the 1990's, and we need to unmuzzle the ATF so they can do that again...