Select your game, distance, gauge, and shot material to get a choke recommendation, shot size, pattern percentage, and maximum effective range.
Choke selection is one of the most overlooked decisions in the field. The choke is the constriction at the muzzle of your barrel that controls how tightly the shot column stays together as it travels downrange. A more open choke like Cylinder or Improved Cylinder spreads pellets quickly, creating a wide pattern ideal for close flushing birds or crossing targets at short range. A tighter choke like Modified or Full keeps pellets together longer, delivering denser patterns at distance — essential for ducks at 40 yards or turkeys strutting in the open.
The standard benchmark for evaluating patterns is the 30-inch circle at 40 yards. A Full choke should place approximately 75% of your pellets inside that circle at 40 yards. Modified delivers around 60%, Improved Cylinder around 50%, and Cylinder as little as 35%. These numbers matter because pattern density directly determines whether you will put enough pellets into a bird's vitals to kill cleanly. Too open a choke at distance and pellets are spread so thin that birds are hit with only one or two — enough to wound but not anchor. Too tight a choke at close range and the pattern column is so dense that it functions more like a slug, tearing rather than distributing energy across a bird's body.
Shot size selection pairs with choke selection. Larger pellets carry more energy per pellet but there are fewer of them per ounce. For doves and quail at 20–30 yards, fine shot like #7.5 or #8 is appropriate — dozens of pellets hit the bird with each shot. Pheasants are much tougher, requiring #5 or #4 lead at longer ranges to penetrate heavy feathers and bone. Waterfowl require non-toxic shot by federal law in the United States, and steel shot is the most common choice. Steel is harder than lead, so it does not deform in the choke — this means steel produces tighter patterns than lead through the same constriction. Experienced waterfowlers typically drop one choke size when switching to steel: where you would use Modified with lead, use Improved Cylinder with steel.
Patterning your specific shotgun with your specific load is the only way to know exactly what you are working with. Tape a 30-inch circle on paper or cardboard, shoot from 40 yards off a rest, and count pellets inside the circle. Compare that count to the total pellet count for your load. The ratio is your actual pattern percentage — and it may differ from published figures depending on your barrel, choke brand, and ammunition lot. Most hunters who pattern their guns discover their choke is either too tight or too open for the ranges they actually shoot. Ten minutes at the pattern board before the season opens is one of the most productive things a shotgunner can do.
Federal law mandates non-toxic shot for all migratory waterfowl hunting in the United States. Steel is the most affordable non-toxic option, but it is significantly less dense than lead — about 30% less dense per pellet. This means a steel pellet of the same size as a lead pellet hits with considerably less energy and penetrates less deeply. To compensate, waterfowlers typically shoot steel shot two to three sizes larger than their equivalent lead load. If you shoot #5 lead on pheasants, #3 or #2 steel is the rough equivalent energy load for ducks. Premium non-toxic alternatives like bismuth and tungsten super shot (TSS) are denser than lead, which allows you to use smaller pellets with better ballistics — TSS in particular has become the preferred load for turkey hunters in lead-restricted areas and for hunters who want maximum downrange performance from a small-gauge gun. Bismuth is safe in all chokes including tight turkey tubes and fixed-choke vintage guns.
| Choke | Constriction | Pattern % at 40 yds | Effective Range (Lead) | Best For |
|---|---|---|---|---|
| Cylinder | 0.000″ | ~35% | 20–25 yds | Deer slugs, home defense, close timber |
| Skeet | 0.005″ | ~45% | 25–30 yds | Skeet, close doves, bobwhite quail |
| Improved Cylinder | 0.010″ | ~50% | 30–35 yds | Upland birds, close waterfowl (steel-rated) |
| Modified | 0.020″ | ~60% | 40–45 yds | Pheasant, trap singles, general purpose |
| Improved Modified | 0.025″ | ~65% | 45–50 yds | Long crossing shots, trap doubles |
| Full | 0.030–0.035″ | ~75% | 50–55 yds | Long ducks, late-season pheasant |
| Extra Full / Turkey | 0.040″+ | ~85% | 35–45 yds | Turkey — ultra-dense head shots |
No — and this is a safety issue, not just a performance issue. Steel shot is harder than lead and does not compress when passing through the choke. Forcing steel through a tight choke can cause barrel bulging or even catastrophic failure. As a general rule, never shoot steel shot through a Fixed choke (old-style non-removable chokes on vintage double barrels), and avoid shooting steel through any constriction tighter than Improved Cylinder unless the choke is explicitly marked as steel-safe and rated for steel shot. Many modern screw-in chokes are steel-rated; look for the marking on the choke tube itself or consult the manufacturer. When hunting waterfowl with steel, use a flush-mounted steel-rated choke in IC or Modified (steel-rated) for the best combination of safety and pattern performance.
Steel #2 and #3 are the workhorses for most duck hunting at 30–40 yards with a 12-gauge. At shorter ranges inside 25 yards, #4 steel gives a dense pattern with plenty of pellets. For larger ducks like mallards and gadwalls at longer ranges, or for diving ducks with their thick bodies, stepping up to steel BB or BBB gives more energy per pellet at the cost of fewer pellets per ounce. Premium loads using bismuth or Heavyweight TSS can use smaller pellets — bismuth #4 or #5 performs similarly to lead #4 or #5 and is safe in all chokes. The minimum recommendation for any duck at 40 yards is enough striking energy to penetrate the feathers, fat, and bone — steel accomplishes this when you match size and velocity to the range, but many cripples are caused by hunters shooting too small a steel pellet too far.
Turkey hunting demands an Extra Full or purpose-built turkey choke — the goal is putting as many pellets as possible into the golf-ball-sized kill zone of a turkey's head and neck at distances usually under 40 yards. Most hunters pattern turkey loads at 20, 30, and 40 yards and find the sweet spot where their load puts 100+ pellets in a 10-inch circle — enough for a clean, humane kill. Traditional lead turkey loads in #4, #5, or #6 work extremely well with an Extra Full choke. If you are hunting with TSS (Tungsten Super Shot) in fine sizes like #9, it patterns best through a tighter choke designed specifically for TSS, typically a constriction around 0.660″ bore for 12-gauge. Never assume a standard turkey choke optimized for lead will deliver the same pattern percentages with TSS — pattern both separately before the season.
Pattern percentage is primarily determined by the choke constriction and the load — not the gauge itself. A 20-gauge Modified choke will still deliver roughly 60% of pellets inside a 30-inch circle at 40 yards, just like a 12-gauge Modified. What changes with gauge is the total pellet count in the payload. A 12-gauge 1-1/8-ounce load of #6 shot contains roughly 281 pellets; a 20-gauge 7/8-ounce load contains about 219 pellets. At the same pattern percentage, the 12-gauge delivers more hits. For most upland hunting this difference is inconsequential. For waterfowl at distance or turkeys, the denser payload of a 12-gauge 3-inch or 3.5-inch shell makes a meaningful difference in pattern density and effective range. Hunters using .410 or 28-gauge should keep shots correspondingly closer to maintain adequate pellet strikes on game.