Play of the game

Lanes and equipment

The U.S. game of tenpins is played according to the rules and specifications of the American Bowling Congress. The game is played indoors on wooden or synthetic lanes with maximum dimensions of 62 feet 10 11/16 inches (19.17 metres) in length and 42 inches (107 centimetres) in width. The surface, coated with lacquer or plastic-type material, must be free of continuous grooves and must be within 40/1,000th inch (one millimetre) of perfect levelness. The distance from the foul line, past which the player may not slide when delivering the ball, to the centre of the spot on which the headpin stands is 60 feet (18.3 metres). The approach to the foul line has a minimum length of 15 feet (4.6 metres).

The pins are 15 inches (38 centimetres) tall and arranged in a triangle formation with the point or No. 1 pin at the head of the formation facing the bowler. The centres of the pin spots are 12 inches (30.5 centimetres) apart. The pins have a laminated wood core covered by a plastic coating. The weight ranges between 3.5 and 3.7 pounds (1.6 and 1.7 kilograms).

The ball is of nonmetallic composition—either hard rubber, polyester, or urethane—with a circumference of 27 inches (68.6 centimetres) and a weight limit of 16 pounds (7.3 kilograms). There is no minimum weight.

Principles of play

A game of tenpins consists of 10 frames. Two deliveries (rolls of the ball) per frame are allowed, the ideal being to knock down all pins on the first for a strike. If pins are left standing after the first delivery, the fallen or “dead” wood is removed and a second delivery permitted. If all remaining pins are knocked down, a spare is recorded. A split can occur on the first ball when two or more pins are left standing, separated by at least one fallen pin. Stepping over the foul line is a foul and results in loss of all pins knocked down on that delivery. There are depressed troughs on each side of the lane; a ball falling therein is a gutter ball and out of play, with resulting loss of one delivery.

Both a strike and a spare count 10 pins plus additional pins scored on the next two (after a strike) or one (after a spare) deliveries. If two strikes in a row are recorded (a double), the player counts 20 pins in the first frame plus the number of pins he knocks down on his first delivery in the third frame. Should he score another strike, he will have 30 pins in his first frame. A perfect game is 300 and consists of 12 strikes in a row, two additional deliveries being permitted in the 10th, or final, frame (one additional following a spare). Competition in league and tournament play includes individuals, as well as teams of up to five players. Two teams are assigned to a pair of lanes, the bowlers alternating lanes for each frame.