How to Pattern a Shotgun With Different Chokes (2026)
Patterning a shotgun with different chokes means firing at a marked board or paper from 40 yards, one shot per choke at the same aim point, then counting pellet holes inside a 30-inch circle to work out a percentage. A Cylinder choke typically prints around 40% of the shot charge inside that circle at 40 yards, Improved Cylinder around 50%, Modified around 60% and Full around 70% — but the real number for your gun depends on the cartridge you feed it, not just the constriction stamped on the tube. Swap shot size, brand, or wad type and the pattern shifts even with the same choke fitted, which is the whole reason patterning matters more than trusting the label.
- Patterning at 40 yards on a 30-inch circle is the only way to confirm how a shotgun and choke actually perform together.
- Full choke should print roughly 70% of pellets in the circle at 40 yards; Cylinder sits closer to 40%.
- Pattern percentage changes with cartridge, shot size, and shot material — retest whenever you switch loads.
- A patchy or uneven pattern signals a choke-cartridge mismatch, not a faulty barrel.
- Steel shot patterns tighter than lead through the same choke, so steel-rated cartridges need their own test.
Why this matters
A choke tube's marking tells you the constriction cut into the muzzle, not what your cartridge does downrange. Two shooters running the same Modified choke can get patterns 15 percentage points apart just from switching shot size or fibre wad to plastic. Choosing chokes for shotgun patterning starts with knowing the constriction options — patterning is the step that proves the choice was right for your gun.
Getting this wrong costs you clays you should be breaking or, worse, wounds game you should be cleanly killing at range. Anyone shooting driven pheasant, wildfowl, or sporting clays in 2026 with a multi-choke over-and-under owes it to the quarry and to their scorecard to run this test before the season, not mid-season when the misses start piling up.
How do you pattern a shotgun with different chokes?
Run the same process for every choke you own, using the cartridge you actually intend to shoot in the field or on the ground.
- Set up a pattern board or heavy paper at 40 yards, marked with a bold aim point and a pre-drawn or overlaid 30-inch circle centred on it.
- Fit the first choke and fire one shot aimed dead centre. Repeat for three shots minimum per choke — a single pattern can mislead because pellet clumping varies shot to shot.
- Count the holes inside the circle. Check the cartridge box or manufacturer spec for the pellet count in that shot size, then divide holes by total pellets and multiply by 100 for the percentage.
- Note the distribution, not just the count. Split the circle into quadrants — a pattern with 70% density but a gap in one quadrant will still miss a crossing bird.
- Swap chokes and repeat the full sequence with the same cartridge, so the only variable changing is constriction.
- Repeat the whole test with a second cartridge if you shoot more than one load, since shot size and wad type move the percentage independently of the choke.
| Choke | Typical constriction | Pattern at 40 yards | Best for |
|---|---|---|---|
| Cylinder | None | ~40% | Close cover, rabbits, close flushes |
| Improved Cylinder | ~0.010 inch | ~50% | Driven game inside 25 yards, skeet |
| Modified (Half) | ~0.020 inch | ~60% | General game shooting, sporting clays |
| Improved Modified | ~0.030 inch | ~65-70% | Longer crossing birds, trap |
| Full | ~0.035-0.040 inch | ~70% | Long-range wildfowling, single-target shots |
Each row is a starting expectation, not a guarantee — your own board test is what confirms it for 2026's cartridge stock.
Cylinder choke: ~40% pattern at 40 yards
Cylinder gives the widest, most open spread of any tube — around 40% of the shot charge lands inside the 30-inch circle at 40 yards. It works well for rabbits flushed from close cover or any shot inside 20 yards where a tight pattern would over-pellet the target. Pros: forgiving on close, fast shots. Cons: thin at anything past 25 yards. Verdict: buy for close-range small game, skip for anything longer.
Improved Cylinder: ~50% pattern at 40 yards
Improved Cylinder sits between Cylinder and Modified, printing roughly 50% at 40 yards. It is the standard skeet constriction and suits driven birds inside 25 yards where you need spread but not a full choke's density. Pros: balances spread and density for close-to-mid shots. Cons: starts thinning past 30 yards on smaller shot sizes. Verdict: buy for skeet and close driven game.
Modified choke: ~60% pattern at 40 yards
Modified is the general-purpose constriction most Irish game shooters settle on, printing around 60% at 40 yards. It handles the bulk of walked-up and rough shooting distances without punishing closer shots too hard. Pros: versatile across most field situations. Cons: not tight enough for genuine long crossers. Verdict: buy as your everyday choke.
Full choke: ~70% pattern at 40 yards
Full choke prints the tightest standard pattern, around 70% at 40 yards, and is built for single shots at range — high pheasant, geese over decoys, or a lone crow at distance. Pros: dense pattern holds together well past 40 yards. Cons: too tight for close flushes, and it wrecks birds shot inside 20 yards. Verdict: buy for long-range wildfowling and single-target shooting only.
Why choke pattern percentage varies
The percentages above are starting points, not fixed outcomes. Several variables move the number for the same choke:
- Cartridge shot size — smaller shot such as size 7 or 8 patterns differently than size 4 or 5 through the same constriction.
- Shot material — steel shot does not deform like lead, so it patterns tighter through the same choke and needs a more open constriction to match a lead pattern.
- Wad design — a plastic shot cup or a fibre wad changes how the shot column releases at the muzzle, shifting density.
- Bore diameter — a choke's constriction is measured against the bore, so the same stamped choke in two guns is not the same real constriction.
- Cartridge velocity — faster loads can open patterns slightly compared with standard-velocity loads through the same tube.
- Distance to target — every choke's percentage drops the further out you measure, so a Full choke tested at 30 yards reads tighter than the same choke at 40.
Related questions
What distance should you pattern a shotgun at?
40 yards is the standard distance for patterning a shotgun, because it approximates the outer edge of an ethical shot on game and a demanding clay target. Testing closer inflates every choke's percentage and testing further exaggerates the drop-off, so 40 yards keeps the comparison meaningful across chokes in 2026 and every season after.
How many pellets should hit a 30-inch circle?
The number of pellets that should hit a 30-inch circle depends on your cartridge's total pellet count and the choke — a Full choke should land around 70% of that count, Modified around 60%, at 40 yards. Check the pellet count for your shot size first, then apply the percentage so you know the target figure before you fire.
Do you need to pattern every cartridge you shoot?
Yes, patterning every cartridge you shoot matters because shot size, shot material, and wad type all shift the percentage independently of the choke fitted. A swap from lead to steel, or from size 6 to size 4, is enough to justify a fresh board test with the same choke screwed in.
FAQ
How do you pattern a shotgun with different chokes?
Fire three shots per choke at a marked board from 40 yards, count pellet holes inside a 30-inch circle, and divide by the total pellet count in the cartridge to get a percentage. Repeat for each choke and cartridge combination you actually shoot.
What is a good shotgun pattern percentage?
A good shotgun pattern percentage matches the choke's design intent: around 40% for Cylinder, 50% for Improved Cylinder, 60% for Modified and 70% for Full at 40 yards. An even spread inside the circle matters as much as hitting the target percentage.
How far should you pattern a shotgun?
40 yards is the standard patterning distance, matching the outer range of most ethical shots on game and demanding clay targets. Testing at other distances still tells you something but will not match published choke percentages.
Does choke size affect shotgun pattern?
Yes, choke constriction is the main factor controlling pattern density, and tighter chokes like Full print a higher percentage of pellets inside the 30-inch circle than open chokes like Cylinder. Cartridge and shot type still shift the exact number for any given choke.
Why is my shotgun pattern patchy?
A patchy pattern usually means a mismatch between choke constriction and cartridge: wrong shot size, wrong wad type, or a choke too tight or too open for that load. Switching cartridge brand or shot size before changing the choke often fixes it.
Do steel shot cartridges pattern the same as lead through the same choke?
No, steel shot patterns tighter than lead through an identical choke because steel pellets do not deform on firing the way lead does. Steel loads generally need a more open choke to match the pattern a lead load produces.
Is Modified choke good for everything?
Modified choke works as a general-purpose constriction for most rough shooting and sporting clay distances, printing around 60% at 40 yards. It is not tight enough for genuine long-range single shots, where Full choke performs better.
How many shots does a full patterning session take?
Three shots per choke per cartridge is the minimum for a reliable average, so testing four chokes with one cartridge takes 12 shots. Add a second cartridge and you are at 24 shots, which is enough fouling to justify a clean afterwards.
One last thing
Most shooters blame the choke when a pattern comes back patchy, but the cartridge is the more common culprit — a fibre wad load through a tight choke can throw a worse pattern than an open choke with a shot cup wad. Before buying another choke tube in 2026, run the board test with two or three cartridge brands through the choke you already own. Wildhunter Gunroom stocks the cartridge range to make that comparison worth doing.