The M134 General Electric Minigun: The M134 is a minigun of US origin. It was developed by General Electric in 1960 as armament for helicopters and to be used in aircraft gun pods. This fully automatic weapon is a relic from the past, but it can still fire up to 166 rounds per second.
 
MCX-Spear by SIG Sauer: The Spear LT is basically a lightweight version of the US military’s recently adopted XM5 rifle, which is a version of SIG’s MCX Spear chambered in 6.8x51mm that won the Next Generation Squad Weapon Program (NGSW). This AR-15 style gun is commercially available and delivers a powerful 
 
Barrett M82 semi-auto: With a muzzle velocity of over 850 meters per second and the capability to deliver 15,000 foot-pounds of energy, this weapon is a hunter's dream come true. A massive semi-automatic rifle, it weighs over 30 pounds, and fires the massive .50 cal BMG round.  Accurate up to a mile in range, and dangerous up to 
 
Anzio 20MM rifle: is a family of manually actuated, bolt-fed civilian-minded anti-material rifles that are available in 14.5mm, 20mm and the Anzio 20-50 calibers. The system fires from a three-round detachable box magazine and features a listed maximum range out to 5,000 yards. Production is handled by the gunsmiths of Anzio 
 
Replica of the old Dahlgren howitzer: This 50-pounder packs a punch with over 11 million foot-pounds of energy.
 
Flamethrowers: Yes. In the United States, flamethrowers are federally unregulated tools and are not considered a firearm by the ATF. No need for any NFA tax stamps, licensing, or even an FFL dealer. However, it’s the purchaser’s responsibility to ascertain that ownership and or use does not violate any state or local laws or 
 
Ghost Guns: These untraceable weapons can be 3D printed at home and are increasingly being used in crimes. Ghost guns are unserialized and untraceable firearms that can be bought online and assembled at home. They are often sold through "ghost gun kits," which include all of the parts
 
Homemade Guns: Homemade guns like ghost guns and 3D-printed guns require no registration, serial number, or background check under federal law, but many states are imposing these restrictions. Homemade guns are legal as long as they're not sold 
 
Wild Kat Keychain: This cute yet dangerous weapon is legal in most states, but it's always best to check with your local police department. These cute kitty keychains are not toys, but are in fact a very serious defense weapon. The design has been 
 
Stun Gun: Stun guns are easily available on Amazon and are legal in most states. People use stun guns for personal protection. A stun gun is an electrical self-defense device that uses a high voltage to stun an attacker. It's a non-lethal weapon that can 
 
Tactical Baton: A baton doesn't require the use of lethal force. As a situation escalates or deescalates, you can quickly adjust your level of force without switching defensive tools. Batons are a less lethal method of self-defense. Baton laws vary by state, but 
 
Silver Single Mace: This medieval weapon is legal in most states, but restrictions apply in some. You have to be 18 to purchase this heavy duty medieval weapon. That spiked ball is attached by a 12-inch chain, "making it easier to render punishment from a 
 
Brass Knuckles: These weighted lead knuckles are legal in some states but require a permit in others. Brass knuckles are pieces of metal shaped to fit around the knuckles and are weapons used in hand-to-hand combat. They are designed so that the user’s 
 
Spear Gun: Harpoon/Spear guns are legal in the US and are designed for taking down larger underwater fish. 
 
Crossbows: While laws vary by state, crossbows are legal for hunting in most states and can fire arrows at over 400 feet per second.