Ten-pin bowling regulations, identification letters and numbers, and general wear from normal use. For much of the history of bowling, bowling balls were made using a three-piece construction method. Starting in the mid-1990s, however, most manufacturers switched to a two-piece method. In response to these innovative ball designs, the American Bowling Congress placed further restrictions on the technical characteristics of the ball such as the radius of gyration and hooking potential. A game of bowling consists of ten frames. In each frame, the bowler will have two chances to knock down as many pins as possible with their bowling ball. In games
Ten-pin bowling is on top of the ball with two fingers in the 12-o'clock position and the thumb ending in the 6-o'clock position, at which point the fingers and thumb release the ball simultaneously. The forearm also creates spin and pushes the ball onto the lane. Spinning is difficult to master, and can cause injury if not done properly. Using a lighter bowling ball (10 to 12 pounds) with a completely rounded core is recommended, along with a conventional grip. Spinning causes results like a weak 5-pin more frequently. The backup style of bowling is where the bowler will flick their wrist