Shotgun Choke and Shot String

When a shotshell is fired from a shotgun, the pellets leave the barrel and begin to spread or scatter. The farther the pellets travel, the greater the spread of the group of pellets (shot) both in length and diameter. This spread is called the shot string. To control the shot string, shotgun barrels have a choke, which will affect the shot pattern when the shot string hits the target.

• Your distance from the target determines the choke you need. However, the choke does not alter the shotgun’s power—it just controls how tight or spread out the pellets will be at a specific distance.
• The spread effect of the most common chokes is illustrated below, showing how many pellets will hit within a certain area at different ranges.

Click on the image below to see a detailed diagram (PDF format) showing the effects of choke on shot string at various distances.

choke: The degree of narrowing at the muzzle end of the shotgun barrel
shot pattern: The spread of shot pellets after they hit a non-moving target
shot string: The three-dimensional spread of shot pellets after they leave the barrel