On paper, shotgun patterns are deceiving. The pattern board reveals only a two-dimensional representation of a three-dimensional shot string, suggesting that all the pellets from a payload arrive simultaneously. Nothing could be further from the truth. As soon as pellets exit the shotgun muzzle, they begin to string out. Depending on the shot type, a shot string can be 12 to 15 feet long and three to four feet in diameter at 40 yards.
So, you must think of your pattern as a comet, rather than a wall of shot, where the most spherical pellets arrive at the target first and create the center or core of the pattern. Deformed pellets are more susceptible to air resistance and arrive later, forming the outer ring of the pattern.
There are many misconceptions about shotgun patterns, probably because no single pattern is the same. After 20 years of studying and testing scatter guns, here’s what I know is true.
Holes in Your Shotgun Pattern Are Irrelevant
When you pattern a shotgun on paper, there are always areas of the target paper devoid of pellet strikes. This only matters if you are shooting at a stationary target, such as the head and neck of a turkey. The likelihood that a duck or clay bird will find a hole in your shot string is unlikely, unless it is flying straight at you or straight away.
Ducks, other gamebirds, and clay targets fly in an assortment of directions: up, down, crossing, etc. This dramatically reduces the chance for birds and clays to line up just right with a hole in the pattern.
Think about one of those rooms you see in movies where the red lasers shoot in all directions to protect something valuable. If you make one false step, the alarm sounds. Now consider trying to throw a Frisbee across the room without it intercepting one of the lasers. That’s about how difficult it is for a bird or a clay to find the void in your pattern.
Chokes Pattern Different Shot Types Differently
If you go to the pattern board and shoot a load of steel No. 3s through a full choke at 40 yards, and it results in a deadly pattern, that’s great. But don’t expect lead, bismuth, or Hevi-Shot 3s to produce a similar pattern from the same distance with the same choke.
Different shot types do not respond the same to choke. And often, the same size steel shot made by a company other than the one used for your pattern test load will produce different results.
It’s just like if you zero a rifle with a 140-grain bullet, then switch to a 165-grain bullet. You won’t see the same result. There may not be as much variance in a shotgun pattern as a rifle cartridge, but there will be a difference. For instance, softer metals may cause your pattern to loosen up, and harder metals may result in a tighter pattern.
Tighter Chokes Don’t Always Yield Tighter Patterns
Since a factory full choke produces a tight pattern, increasing the choke constriction will make the pattern even tighter. However, there comes a point when too much constriction has the opposite effect and can cause blown patterns. This is particularly true with larger steel shot—No. 2s and up.
Most of the testing I have done with steel 2s, 1s, BBs, and BBBs has shown that pattern density improves when shooting through modified or improved modified chokes. I’ve seen the same thing happen with some TSS turkey loads. Too much choke killed performance.
Also consider that a tighter pattern makes it more likely you will fringe birds and cripple them. Tight patterns are great if you’re a crack shot every time you pull the trigger, but if you’re off even a little, the pellets may not penetrate the vitals.
One-Shot Patterns are Worthless
I once watched a YouTube hunting show where the host patterned his turkey gun by placing an empty water bottle on a stick and shooting it to determine if it was “on target.” Granted, the ol’ boy was a fine hunter of spring toms and has killed many gobblers on camera, but that’s not a proper way to teach anyone to determine gun accuracy.
The “industry standard” is to shoot the same load, choke, and gun combination 10 times from 40 yards, find the core of the pattern, draw a 30” circle around it, count the pellet strikes, and average them. You may not have the money or time for all that, so do what you can. You can learn more about patterning a shotgun for turkey hunting here.
Most shooting ranges have an area designated for patterning shotguns, and I encourage everyone to take advantage of it before shooting a round of skeet or trap, which every hunter should do before the opening day of their respective bird season. Pepper three to five shots at the pattern board or a painted steel plate, count the number of pellet strikes, and take note of the pattern distribution in relation to your aim point.
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