The Supreme Court heard oral arguments Wednesday Garland vs. Cargill, which raises the question of whether a semi-automatic rifle with a bump stock is a machine gun. A machine gun is defined as “any weapon that automatically fires more than one shot, without manual reloading, by a single trigger function.” 26 USC § 5845(b). If a gun fires automatically, that is, without any manual manipulation, and does so with only one trigger function – which could be pulling or pushing – it is a machine gun.
In the very first two sentences of his opening statement to the government, Brian Fletcher unwittingly explained why a bump stock is in place. Not a machine gun. With a bump stock, one “places the trigger finger on the built-in ledge and uses the other hand to press the front of the rifle forward. As long as the shooter maintains that constant forward pressure, the rifle will fire continuously….” What he didn’t say is that if you simply pull the trigger but don’t manually continue to push the forend forward, the gun fires a single shot and stops firing.
A video is worth more than a thousand images. See how a machine gun shoots. You can hold it with one hand and simply pull the trigger and it fires continuously until the magazine is empty. This happens automatically via a single trigger function.
Not so with the bump stock. Try holding it with one hand and pulling the trigger. One shot and he stops shooting. Watch here at 3:15-4:48 pm. Unlike the machine gun above, it did not continue firing even if the trigger remained pulled back.
Now watch a gun shot with a butt in slow motion, starting at 4:54. “So look here like my hand carry on down the barrel of the gun,” says the narrator. “The gunman fires and the recoil brings the trigger back to my still finger again and again, causing the trigger to be pulled again and again very quickly….” As shown by the video, the trigger only works once for each shot.
Or as Mr. Fletcher says, pull the trigger and also “Press the front of the rifle forward” AND “maintain[] that constant forward pressure.” It is not “automatic” thanks to a “single trigger function.” He also said that firing is “automatic” because one “presses forward to fire the first shot, the bump stock uses the ‘the gun’s recoil energy to create a continuous back and forth cycle.” What happens if you stop pressing forward, even with the trigger pulled back? It stops shooting.
For years, the Bureau of Alcohol, Tobacco, Firearms & Explosives (ATF) has classified non-mechanical bump stocks as non-machine guns. Richard Vasquez was a top examiner at the ATF’s Firearms Technology Branch and was involved in this classification. As an attorney for clients regulated or prosecuted by the ATF, I knew that Mr. Vasquez was a tough but fair law enforcement officer who knew where to draw the line. Now he’s retired and you can watch his explanation of why the bump stock isn’t a machine gun.
While the oral discussion posed many hypotheses, two real-life firearm designs emerged. One involved the Atkins Accelerator, a mechanical bump stock that used a spring-loaded device to facilitate continuous fire. The ATF initially approved the design as not a machine gun, but later reversed that classification and determined that it was a machine gun. Unlike the non-mechanical bump stock in question here, there was no need to maintain continuous, forward pressure on the barrel or handguard to continue firing.
The other device mentioned in the argument was the one cited in United States vs. Campo (5th Cir. 2003), which featured an electrically operated trigger mechanism. “It required only one action – pressing the switch he installed – to fire multiple shots” and then it was revealed to be a machine gun. No manual manipulation was involved. This is very different from a manually operated bump stock.
There has been a lot of talk about the rate of fire, even hundreds of rounds per minute (only a theoretical concept, because the magazines only hold about thirty or so). But as Fletcher admitted, “we recognize that this is not a rate of fire law.” Indeed, according to the legal definition, a machine gun could fire very slowlybut it could still activate automatically with a single trigger pull.
The transcript of the oral argument reveals a robust debate, but the statutory text is the elephant in the living room. A non-mechanical bump stock is simply not a machine gun.