6. Have you been discharged from the Armed Forces under dishonorable conditions?
7. Are you subject to a court order restraining you from harassing, stalking, or threatening your child or an intimate partner or child of such partner?
8. Have you ever been convicted in any court of a misdemeanor crime of domestic violence?
You also have to provide the government with the reason why you think it appropriate for you to have a fully automatic weapon, sawed-off shotgun, or other "destructive device":
13. Transferee Necessity Statement: I ___________, have a reasonable necessity to possess the machinegun, short-barreled rifle, short-barreled shotgun, or destructive device described on this application for the following reason(s) ________________ and my possession of the device or weapon would be consistent with public safety (18 U.S.C. 922(b) (4) and 27 CFR 478.98).
Karl Frederick, the NRA's president back when these laws were put into place, was enthusiastic. "I have never believed in the general practice of carrying weapons," he said. "I think it should be sharply restricted and only under licenses." When asked if he thought the National Firearms Act of 1934 violated a person's Second Amendment rights, he famously said, "I have not given it any study from that point of view."
The result of the restrictions on ownership of fully automatic weapons (and other "destructive devices") has been that they've pretty much vanished as the scourge on public safety that they were in the late 1920s and early '30s.
Thus, it's rare that either automatic weapons or the less-efficient-at-killing-lots-of-people revolvers and bolt-action rifles are used for mass murders. This is largely because the former are hard to buy/own, and for the latter the time necessary to re-co*k and re-load presents victims an opportunity to stop a mass shooting.
Remember, the only reason the shooter who tried to kill Congresswoman Gabby Giffords was stopped after "only" killing six people was that he had to replace his 33-shot magazine with a fresh one, and Bill Badger, a 74-year-old man standing near him (whom he'd just shot), tackled him and held him to the ground.
Thus, as the volume of production of semi-automatic weapons has increased in the past 30 years or so, and their price has come down, the older-fashioned pistols and bolt-action rifles have been replaced by a more recent generation of semi-automatic pistols, rifles, and assault weapons.
But if most handguns in circulation were revolvers, and most rifles were bolt- or break-action, there would be far fewer (or at least far less deadly) mass shootings.
Revolvers typically have a cylinder that holds from 5 to 10 rounds of ammunition, and each chamber in the cylinder must be individually loaded. While there are autoloaders and other ways to speed up the process, the gun is still largely limited, at least in an "active shooter" situation, to the rounds in its cylinder.
With a single-action revolver, the gun can't even be fired until it's cocked by pulling back the hammer (although a double-action revolver will accomplish this with the first part of the trigger pull).
Revolvers are very efficient killing machines, having been in widespread use since their popularization by the Colt Company in the 1830s, but while they're great for sport and self-defense (and were police weapons of choice just up until the past 30 or so years), for mass killings they can't hold a candle to semi-automatics.
Semi-automatic pistols are, in their modern form, a creation of the last century. They use the recoil force of a shot (some also use the exhaust gases) to load a new round into the chamber and co*k the gun, all in one seamless and nearly instantaneous motion.
As a result, semi-automatics can be fired as fast as one can pull the trigger, and the amount of trigger pressure a revolver would require to co*k the hammer is unnecessary. And, because they don't have a built-in cylinder like a revolver, the magazine in a semi-automatic that stores the ammunition (some as large as 50-shots) can be quickly replaced.