Ammunition

• The major difference between a BB gun and a pellet gun is the type of ammunition used. BB guns use spherical ammunition with a diameter of around 0.177 inches.This ammunition is usually made of steel, and coated with either zinc or copper. BB guns gain their name because the ammunition is called a "BB."
  
  Pellets vary in shape and size and are typically larger than BBs. Pellets are non-spherical and come in either 0.177- or .22-inch sizes. Both 0.20- and 0.25-inch pellets are available, but they are not as common as the former two sizes. A pellet is usually designed with a hollow bottom-half; the tips are hollow, pointed, flat or round. It is typically made of tin, although some manufacturers produce hybrids with a plastic tip.
  
  

Barrel

• BB guns are typically used in close-range practice; most BB guns use a smooth-bore barrel. Smooth-bore barrels release ammo without spinning it. This prevents the gyroscopic effect that maintains a bullet's trajectory, making shooting more accurate.
  
  Pellet guns come standard with rifled barrels, and have better accuracy than BB guns. Rifled barrels spin the bullet as it's released from the barrel, creating a gyroscopic effect. Pellet guns are preferred over BB guns when hunting small game or pests.
  
  

Price

• Pellet guns are typically more expensive than BB guns. The latter might cost as little as $25, as of 2011. Pellet guns normally range from $100 to $200 in 2011 prices. Cost is dependent on the type of gun you want and the accessories purchased. Guns prices also vary depending upon the sophistication of the design. BB or pellet guns powered by CO2 cartridges often go for several hundred dollars.
  
  

Safety Concerns

• Both types of air guns can harm people if they are not handled properly. Pellets can penetrate the skin, and BBs can easily ricochet. Wear protective glasses when using an air rifle or pistol. Check local laws and regulations when buying or shooting these guns. Some states require air-gun users to be at least 18 years old. Municipal or county ordinances might also come into play.