When it comes to shotguns, many folks put copious amount of thought into shot size, velocity, material and even shell length. On the other hand surprisingly few give a second though to their choke constriction that they shoot through. Most modern shotguns are threaded and supplied with 3-5 different sizes of chokes to allow the shooter to pattern size and density to their individual application. Chokes can have a drastic influence on how effective even a well-placed shot will be.
The basic concept of a choke is that various amounts constriction at the muzzle will influence the rate at which the shot will spread once it is released into the atmosphere. Once the shot leaves the barrel, it begins to spread at a somewhat constant rate. Ideally the shooter wants the largest pattern possible while still maintaining enough pattern density to have the desired effect on the target. A pattern that is too small is very unforgiving to the shooter’s marksmanship and, for hunting applications, very damaging to meat. Patterns that spread too rapidly before they reach the target may arrive with too low of a pellet density to knock down or break the intended target. To maximize effectiveness, a shooter must realistically identify the distance at which they intend to encounter their target and choose an appropriate choke to deliver an optimum pattern at that distance.