Title: BB gun
Content:  It is possible to shoot competitively with a BB gun. The National Rifle Association youth shooting program has classifications for smoothbore BB guns, open to ages 14–18, and these classes are popular with youth groups such as 4-H and the Boy Scouts of America.
Title: Air gun laws
Content:  In Bulgaria anyone over the age of 18 can obtain an airgun if its muzzle energy is below that of 24 Joules. If is over 24 Joules the airgun subject to notification regime in the Police. Cannot be bought online,but some gun shops deliver them with their own supplier legally.
Title: Firearms regulation in Canada
Content:  By law, a potential customer must be 18 years of age or older to purchase a firearm or legally maintain possession of one. People under the age of 18 but over the age of 12 may procure a minor's licence, which does not allow them to purchase a firearm but allows them to borrow a firearm unsupervised and purchase ammunition. Children under the age of 12 that are found to need a firearm to hunt or trap may also be awarded the minor's licence. This is generally reserved for children in remote locations, primarily aboriginal communities that engage in subsistence hunting.
Title: Gun laws in Pennsylvania
Content:  Pennsylvania state law refers to a handgun as a "firearm", while "long gun" is used to describe a shotgun, or rifle of a certain length or longer. Minimum age for purchasing a long gun is 18, and the age restriction for purchasing a handgun is 21. However, someone can own a handgun if he or she is 18 and received the handgun as a gift. To purchase a firearm, buyers must be at least 18 years of age. They can never have been convicted of a violent crime, must not be an undocumented immigrant, declared mentally ill by the court, a drug addict or 
Title: Gun laws in New York
Content:  the intention to load or fire it. In New York City, only adults at least 21 years of age or older can purchase or own a firearm with a permit or license issued by the NYPD. In the rest of the state, adults 18 years of age or older can purchase long guns (rifles & shotguns) without a permit, and only adults 21 years of age or older can purchase or possess a handgun (with the proper licensing requirements). Minors who are at least 16 years of age can possess long guns. Age restrictions on purchasing apply for both FFL dealers and 
Title: Gun laws in New York
Content:  Gun shows: New York requires anyone who buys a gun at a gun show to pass a background check. Youth and firearms: Youths between ages 14 and 21 may shoot a handgun at a range only if they are under the supervision of a military officer or licensed professional, have not been convicted of a felony, and do not seem to be a danger to themselves or others. Youths between 12 and 15 may only possess to load or fire a firearm when supervised by an adult with specific qualifications. Children under the age of 12 are not permitted to possess a firearm 
Title: Gun laws in Michigan
Content:  At the age of 18 or up, it is legal to buy a pistol with a purchase license from a private seller, at the age of 21, it is legal to buy a firearm from a Federally licensed (FFL) dealer. No purchase license is required to purchase a long gun (a firearm that is more than 26 inches long) in Michigan. According to state law, a long gun may be purchased by anyone aged 18 or over who is not subject to restrictions based on criminal history, mental health history, or other disqualifying factor. A person must be at least 18 years old to 
Title: Gun laws in Ohio
Content:  To purchase a long gun (rifle or shotgun) in Ohio, a person must be at least 18 years of age, with some restrictions still remaining. To be able to qualify to purchase a handgun (pistol or revolver) in Ohio, a person must be at least 21 years of age. This applies to both private sales and those through a Federal Firearms Licensee. However, the law regarding purchasing age is silent on ammunition, components and accessories. In Ohio, there are also a few other laws that are important to be mindful of. It is illegal to consciously fire a firearm while inside of a motor vehicle. Antique or replica rifles, shotguns, and handguns are supposed to be treated with the same urgency and under the same law a modern firearm would be. Antiques or 
Title: Air gun laws
Content:  Air guns can be freely bought and owned by any person older than 18 years old. Only pistols with muzzle energy exceeding 7.5 J are not allowed. There is no maximum muzzle energy limit for rifles. Open carry of airguns is not allowed. The use of air guns is restricted non-public places, being shooting ranges, inside a house or a backyard that is not easily accessible from the street.
Title: Legal issues in airsoft
Content:  Airsoft guns under 0.5 joules are deemed to be toy guns and can be used by all people above the age of 14. Some shops do still require a legal guardian to be in attendance and give permission when buying a <0.5 joule airsoft gun, however most shops sell these toy guns to anybody above the age of 14. In addition, they must not be carried in public as they can be authentic looking weapons. If the muzzle energy is between 0.5 and 7.5 joules, Airsoft guns are no longer seen as toy guns. In that case, they are treated as air rifles, the minimum age for purchasing and / or using an airsoft gun is 18 years. These guns need a 

Question: what age do you need to be to buy a bb gun?
Answer: 18.