Quick Answer
A shotgun shell is described by gauge (12 and 20 are the most common), length (2¾ inch standard; 3 and 3½ inch magnum shells only in guns chambered for them), shot size (small numbers are bigger pellets: #8 for clays, #6 for pheasant, BB for geese, 00 buck for defense and deer, or a single slug) and payload and velocity. Match the shell to the job: target loads (#7½–#9, 1–1⅛ oz) for clays, #4–#6 lead or #2–#4 steel for upland and ducks, #4–#6 tungsten or lead turkey loads, 00 buck or slugs for deer and defense. Non-toxic shot (steel, bismuth, tungsten) is required for waterfowl everywhere in the US.
Key Takeaways
- Gauge is a diameter: 12 ga (.729 in) is the all-rounder, 20 ga lighter recoil, 28 ga and .410 for experts and small birds; .410 is a caliber, not a gauge.
- Never fire a shell longer than the chamber stamped on the barrel; a 2¾-inch gun cannot take 3-inch shells.
- Shot size: #9 (tiny) to BB (large) birdshot; #4 buck to 000 buck; slugs are a single projectile.
- Lead is cheapest and hits hardest per size; steel is required for waterfowl and needs two sizes larger; bismuth and tungsten (TSS) are premium non-toxic.
- Dram equivalent and fps indicate power; 1,200 fps 1⅛ oz is a standard 12-gauge target load.
- Buckshot and slugs for deer and defense; birdshot is for birds and clays, not home defense.
Shotgun ammunition is more varied than any other kind, and the box tells you everything you need if you know how to read it: a gauge, a length, a payload, a shot size, a velocity or dram equivalent and sometimes a shot material. Each matters for a different reason, and the wrong combination ranges from ineffective to dangerous. This guide explains each element, lays out shot sizes with their uses, covers the non-toxic shot rules, and recommends loads for the common purposes. Velocities and payloads are typical; the box is the final authority.
Gauge Explained
| Gauge | Bore diameter | Typical payload (2¾ in) | Recoil | Common uses |
|---|---|---|---|---|
| 10 gauge | .775 in | 1⅝–2 oz (3½ in) | Heavy | Geese, turkey; rare today |
| 12 gauge | .729 in | 1–1⅛ oz target; 1¼–1½ oz field | Moderate to heavy | Everything: clays, birds, deer, defense |
| 16 gauge | .662 in | 1–1⅛ oz | Moderate | Upland classic; limited ammo selection |
| 20 gauge | .615 in | ⅞–1 oz target; 1–1¼ oz field | Light to moderate | Youth, upland, turkey, deer with slugs |
| 28 gauge | .550 in | ¾ oz | Light | Skeet, quail, dove; expensive ammo |
| .410 bore | .410 in | ½ oz (2½ in), 11/16 oz (3 in) | Very light | Small game, pests, expert skeet; not for beginners |
Gauge comes from the number of lead balls of bore diameter that make a pound: twelve for 12 gauge. Smaller numbers mean bigger bores. The .410 is named by its bore in inches.
Shell Length and Chambers
Shells are sold in 2½, 2¾, 3 and 3½-inch lengths; the measurement is the fired, unfolded hull, so a loaded 3-inch shell looks shorter. The barrel is stamped with the longest shell it can chamber (for example, ’12 GA 3 IN’). Shorter shells can always be used in a longer chamber; a longer shell in a shorter chamber may seat but will create dangerous pressure when the crimp opens into the forcing cone. Longer shells hold more shot and powder for waterfowl and turkey; 2¾-inch is the standard for targets, upland and defense and has the mildest recoil.
Shot Sizes and What They Are For
| Shot | Pellet diameter | Pellets per oz (lead) | Uses |
|---|---|---|---|
| #9 | .08 in | ~585 | Skeet, quail, snipe |
| #8 / #8½ | .09 in | ~410 | Trap, sporting clays, dove |
| #7½ | .095 in | ~350 | Trap, dove, quail, grouse |
| #6 | .11 in | ~225 | Pheasant, rabbit, squirrel, turkey (lead) |
| #5 | .12 in | ~170 | Pheasant, turkey |
| #4 | .13 in | ~135 | Pheasant, ducks (lead), turkey |
| #2 | .15 in | ~90 | Ducks (steel), geese (steel) close |
| BB | .18 in | ~50 | Geese (steel), large ducks |
| T / BBB | .19–.20 in | ~35–40 | Geese (steel), coyote |
| #4 buck | .24 in | ~27 per 1⅛ oz shell | Deer (close), defense |
| #1 buck | .30 in | ~16 | Deer, defense |
| 00 buck | .33 in | 8–9 (12 ga 2¾) | Deer, home defense standard |
| 000 buck | .36 in | 8 | Deer, defense |
| Slug | Single, ⅞–1 oz | 1 | Deer, bear defense; rifled slugs for smooth bores, sabot slugs for rifled barrels |
Shot Materials: Lead, Steel, Bismuth, Tungsten
Lead is dense and cheap and remains legal for upland birds, clays, turkey and deer in most places (some states and public lands restrict it). Steel is required nationwide for waterfowl; it is lighter, so go two sizes larger than lead (#2 steel for #4 lead ducks), it must not be fired through old fixed-choke or thin-walled barrels not rated for it, and it patterns tighter. Bismuth is nearly as dense as lead, safe in old guns and legal for waterfowl, at a premium. Tungsten alloys (Hevi-Shot, TSS) are denser than lead, allowing smaller shot with more pellets and longer reach; TSS turkey loads in #9 have made 20-gauge and even .410 turkey guns effective, at a high cost per shell.
Reading Power: Dram Equivalent and Velocity
Older boxes list ‘dram equivalent’ (e.g., 3 dram), a legacy comparison to black-powder charges; newer boxes list muzzle velocity in fps. A 12-gauge 2¾-inch target load at 1,145–1,200 fps with 1⅛ oz of shot is the standard; ‘light’ or ‘low recoil’ loads drop to 1 oz at 1,100 fps; field loads push 1¼ oz at 1,300+; waterfowl steel runs 1,400–1,550 fps. Higher velocity increases recoil and, with lead, can degrade patterns past a point. Managed-recoil buckshot and slugs (around 1,145–1,200 fps) are easier to shoot well and are preferred for home defense.
Best Loads by Purpose
- Trap: 12 ga 2¾, 1⅛ oz #7½ or #8, 1,145–1,200 fps.
- Skeet and sporting clays: 1 or 1⅛ oz #8 or #9 at 1,145–1,200 fps; 20 ga ⅞ oz.
- Dove and quail: 1–1⅛ oz #7½ or #8.
- Pheasant: 1¼ oz #5 or #6 lead at 1,300 fps; #4 for late season.
- Ducks: 3-inch 1¼ oz #2 or #4 steel at 1,400–1,500 fps; bismuth #4 or #5.
- Geese: 3 or 3½-inch BB or BBB steel, or #2 tungsten.
- Turkey: 3-inch #5 or #6 lead; 3-inch #7–#9 TSS; 20 ga TSS #9.
- Deer (smooth bore): rifled slug or 00/000 buckshot inside 40 yards; (rifled barrel) sabot slug.
- Home defense: 2¾-inch 00 buckshot, ideally a managed-recoil load with a tight-patterning wad (Federal FliteControl, Hornady Critical Defense); #1 buck is a good alternative; not birdshot.
- Small game and pests: #6 lead in 12 or 20 ga; .410 #6 for close pests.
Safety Notes
- Match gauge exactly; a 20-gauge shell dropped into a 12-gauge barrel lodges in the bore and the next 12-gauge shell behind it bursts the barrel. Keep gauges separate (20-gauge hulls are yellow by convention).
- Never exceed the chamber length on the barrel.
- Confirm steel-shot compatibility before firing steel in older guns or through full chokes.
- Use rifled slugs in smooth bores and sabots in rifled barrels; the reverse patterns poorly or fouls the rifling.
- Pattern your gun with the load and choke you will use; shells of the same size pattern differently.
Frequently Asked Questions
What is the difference between 12 gauge and 20 gauge?
12 gauge has a larger bore (.729 vs .615 inch), carries more shot and recoils harder; 20 gauge is lighter and softer-shooting with a slightly smaller payload. 12 is the all-rounder; 20 suits youth, upland and recoil-sensitive shooters.
Can I shoot 3-inch shells in a 2¾-inch shotgun?
No. Only shells up to the length stamped on the barrel are safe. Shorter shells can be used in longer chambers, but not the reverse.
What shotgun shells are best for home defense?
2¾-inch 00 buckshot, ideally a managed-recoil load with a flight-control wad, or #1 buck. Birdshot is not recommended because it lacks penetration.
What shot size for ducks and geese?
Non-toxic shot is required: #2 to #4 steel for ducks, BB to BBB steel for geese, or bismuth and tungsten in sizes closer to lead. Go about two sizes larger with steel than with lead.
What does dram equivalent mean?
A legacy measure comparing the load’s power to a black-powder charge in drams. Modern boxes list velocity in fps instead; a 3-dram 12-gauge target load is roughly 1,200 fps with 1⅛ oz of shot.
Conclusion
Read the box in order: gauge to match the gun, length to match the chamber, shot size and material to match the game or target, and velocity to match your tolerance for recoil. Target loads for clays, #5–#6 for upland, steel #2–#4 for ducks, TSS or #5 for turkey, buck or slugs for deer and defense. Pattern the combination you choose, keep gauges separate, and the shotgun does the rest.
