A shotgun choke is used to control the pattern of the discharge at differing distances. The most commonly used chart of that is the Briley Choke Effectiveness Chart. It connects the chokes to a 30 In. diameter pattern at differing ranges so that the shooter can used the choke that gives him/her the most effective shot at the range of his/her target.
It states;
Cylinder—-100% at 20 yards, 0.00 restriction
Improved Cylinder—30 yards, 0.010 restriction
Modified————40 yards, 0.020 restriction
Full—————-50 yards, 0.035 restriction

Chokes such as the Skeet, 0.005 restriction then falls into the 25 yard range and is used for Skeet where the target varies between 18 to 30 yards.

The Lite Modified choke, 0.015, falls to the 35 yard range, many trap shooters use it for the 16 yard line as the ATA states that most 16 yard targets are broken at 30 to 35 yards.

The Improved Modified, 0.025, and the Lite Full, .030. fall in the distances between 40 and 50 yards and seem to be fine tuning, if it works for you use it.

Briley Chokes

BRILEY CHOKES, the first major, after market screw-in choke manufacturer, and the best in most opinions. I stock EXTENDED chokes for most of the popular guns; I have some FLUSH and some SPRECTRUM too. Anything that you need that Briley makes can be ordered through me, and it will never cost you shipping. For orders inside the continental U.S.


Black Oxide and Camouflaged chokes are available for all guns, to order call (904) 260-9498. Add $5.00 for either. Briley’s “Duck”-Lite Mod, Camo. and “Goose”-Improved Mod, Camo. chokes are also available at the above number.