Pellet Count & Pattern Density
How many pellets are in your shell, and what percentage landed in a 30" circle.
How this works
Pellet weight is calculated from the sphere's diameter and the density of the shot material you chose (lead, steel, or bismuth all differ in density), which gives the total pellet count in a given shot charge weight. Pattern density then compares how many of those pellets you actually counted inside a standard 30-inch circle against the theoretical total.
Reading the choke equivalence
The published choke classifications (Full, Modified, Improved Cylinder, and so on) are defined by exactly this percentage at 40 yards, which is why pattern-testing your own gun and load is the standard way hunters verify what choke constriction they're actually getting — printed choke markings are a starting point, not a guarantee.
Frequently asked questions
What pattern density counts as a "Full" choke pattern?
The published classification used here considers 70% or more of pellets landing in a 30-inch circle at 40 yards to be roughly equivalent to a Full choke, with lower percentages corresponding to more open chokes.
Why would my actual pattern differ from the choke's printed label?
Printed choke labels are a starting point, but your actual pattern depends on your specific gun, barrel, and load combination — pattern-testing at your hunting range is the standard way hunters verify what they're really getting.
Does switching from lead to steel shot change my pellet count?
Yes — steel is less dense than lead, so a steel pellet of the same diameter weighs less, which changes the total pellet count for a given shot charge weight. Select the correct material for an accurate count.
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