A hand-driven machine gun, the Gatling gun was the first firearm to solve the problems of loading, reliability, and the firing of sustained bursts.

早期的盖特机炮虽然要靠手摇才能开火，但它毕竟是同时解决了装弹、稳定性、连续开火问题的首款火力武器。

youdao

Any alteration or change made to a firearm after manufacture can make the gun dangerous and will usually void any factory warranties.

任何在出厂之后的修改或改造都有可能对枪造成危险，并且通常会使厂家的保证失效。

youdao

Even while running for President in 2008, McCain upset the all-powerful National Rifle Association (NRA), and its legion of members, when he supported closing the gaping loopholes that permit almost anyone to buy a firearm at a gun show.

FORBES: Will A Conversation On Guns Ever Again Be Possible In America?

Under federal law, anyone wanting to purchase a firearm from a licensed gun dealer must pass a background check.

CNN: Mass murder and powerful firearms

Ten states and the District of Columbia have their own laws requiring background checks for any firearm sold at a gun show, Nichols said.

CNN: 'Universal background check:' What does it mean?