He also recounted how he acquired two backup weapons: a Mossberg 500 shotgun he bought in early December and a Savage Axis XP semi-automatic rifle he received from his father as a Christmas present when he was 16 years old.
Gendron was arrested on Saturday and charged with murder after police said he killed 10 people and injured three others in a shooting at a Tops Friendly Market in Buffalo. Authorities said the attack was racially motivated and that Gendron targeted the store because it was in a predominantly black neighborhood.
Vintage Firearms owner Robert Donald, 75, confirmed to The New York Times and ABC News on Sunday that he sold the Bushmaster to Gendron. He said a background check turned up no flags and officers from the Bureau of Alcohol, Tobacco and Firearms visited his store – a former one-room house – on Saturday night to collect the documents of the sale.
“I happened to have this particular weapon at that particular time,” Donald told ABC. “And this particular guy bought it. Once the gun leaves the gun store, you have no control.
In New York State, customers 18 and older are allowed to purchase rifles and shotguns without a license, although they must pass an instant criminal background check at the time of sale. (Gun control laws are more restrictive in New York.)
Gun buying background checks are supposed to flag people with a history of mental illness, but generally prohibit sales only to people in serious cases, such as people who have been institutionalized by a judge. Law enforcement officials said they investigated Gendron last June after he allegedly made a threatening statement. Buffalo Police Commissioner Joseph Gramaglia said New York State Police arrested Gendron, then 17, and transferred him to a hospital for a mental health evaluation. He was released a day and a half later.
In 2013, New York State passed a law banning the sale of assault-style semi-automatic rifles with 10 common features, including protruding pistol grips, flash suppressors, and folding or telescoping stocks. One of the suspect’s online posts includes a photo of his Bushmaster XM-15 E2S Target rifle with what appears to be a pistol grip. He did not say if he bought the rifle this way or if he added the grip later.
In a post, Gendron admitted to having illegally modified the weapon in some other way. He wrote that he used his father’s electric drill to remove a state-mandated lock that prevented the attachment of magazines holding more than 10 rounds of ammunition.
New York State law prohibits the use of high capacity magazines with more than 10 rounds. Gendron wrote that he wanted to use 30-round magazines during the massacre so he wouldn’t have to reload frequently.
In one post, Gendron called New York’s gun laws or those who obey them eight times “cuck” or “cucked,” a misogynistic slur popular among some far-right extremists.
“Since living in New York, I had to buy a cuckold version before illegally modifying it,” Gendron wrote. “Since I live in cuckold New York and I’m only 18, I can’t or a standard ‘assault rifle.’ okay, but what kind of cuckold does that?”
According to the Giffords Law Center to Prevent Gun Violence, eight states and the District of Columbia have banned “large-capacity ammunition magazines” for rifles and handguns. District and most state laws—California, Connecticut, Maryland, Massachusetts, New Jersey, New York, and Vermont—limit the number of rounds allowed to 10. Colorado allows 15 rounds for all firearms; Vermont allows 15 for handguns.
In a detailed and often rambling explanation of his weapons and equipment, the suspect wrote that he deliberately loaded heavier cartridges to be used in a first volley to penetrate the glass at the front of the supermarket where he expected to be monitored by a security guard. He then loaded lighter rounds deeper into the store so he could use them to target shoppers and other victims in the store. Lighter bullets travel faster and can pass through bodies more easily, causing maximum damage when passing through flesh.
A semi-automatic rifle can fire as fast as the shooter can pull the trigger. In live-streamed video the suspect posted online, he quickly shoots his first victims outside before entering the store to shoot others, appearing to empty his magazine after around 30 rounds. The entire sequence, from initial shots to reloading, lasts about 20 seconds.
The Bushmaster family of rifles is part of the ubiquitous family of AR-15 style weapons – the most common rifle in the United States. Used Bushmaster XM-15s can be had for around $1,000 or less, putting them on the low end of some AR-15 models that sell for hundreds of others. The rifle is a no-frills option that lacks a rail system, which limits accessories like optics, lasers, and foregrips. The alleged shooter complained that there was no way to attach a light other than tape to the handguard.
The Bushmaster XM-15 is the same rifle model that was used in two other notorious mass shootings: DC’s 2002 sniper case, in which two gunmen killed 10 random people during a a month-long wave of terror in the Washington area; and the 2012 massacre at Sandy Hook Elementary School in Newtown Square, Connecticut, in which a sniper killed 20 first-graders and six staff members.
In February, the families of nine victims of the Sandy Hook massacre settled a lawsuit against Remington Arms, maker of the Bushmaster, for $73 million. Federal law makes it difficult to sue gun manufacturers for product liability. But the plaintiffs used a new legal strategy, arguing under Connecticut law that the Bushmaster amounted to a weapon of war and that Remington was improperly marketing the rifles to civilian men.
In one of his posts, the suspect offered a mixed review of the Bushmaster XM-15 he had purchased. While saying he chose the rifle for its lethality, he complained that its 20-inch barrel was too long and unwieldy. “It’s literally the worst option for me since I’ll be mostly indoors and in my car.” He said he would bring the Mossberg shotgun and the Savage Axis XP rifle mainly as reinforcements.
When Buffalo police arrested Gendron, they said, he was carrying a semi-automatic rifle that matched the description of the Bushmaster. The other two weapons were recovered from his car.
Jon Swaine, Reis Thebault and Alice Crites contributed to this report.
