Steel shot and lead shot differ in density, hardness, and how they perform downrange. Lead is roughly 54% denser than steel (11.3 g/cm³ versus 7.31 g/cm³), which means a lead pellet of the same size carries more mass and hits harder at distance. Steel is far harder, so it doesn’t deform during firing, producing tighter patterns but also posing risks to older shotgun barrels. The other major difference is legal: lead shot has been banned for waterfowl hunting in the United States since 1991 due to widespread bird poisoning, making steel the standard for hunting over water.
Density and Weight
The single biggest physical difference is density. Lead packs 11.3 grams per cubic centimeter compared to steel’s 7.31. In practical terms, a lead pellet is about 1.5 times heavier than a steel pellet of the same diameter. That extra weight means more momentum, which translates to deeper penetration and better energy retention as the pellet slows down over distance.
To compensate, shooters using steel typically go up one or two shot sizes. A No. 3 steel pellet is closer in weight to a No. 5 lead pellet, for example. This size-up approach helps close the gap in downrange energy, though it means fewer pellets fit in the same shell.
Hardness and Pellet Deformation
Pure lead is extremely soft, with a Brinell hardness around 4 to 4.5. Steel pellets are many times harder. This difference matters the instant the trigger is pulled. Under the intense pressure of ignition, soft lead pellets deform, flattening slightly against each other and the barrel walls. Deformed pellets are less aerodynamic: the less spherical a pellet is, the more air resistance it encounters in flight, causing it to slow down faster and drift off course.
Steel pellets are too rigid to deform under firing pressure. They stay perfectly round, which means they fly more efficiently and hold a tighter, more concentrated pattern. This sounds like a pure advantage, but it’s a trade-off. That same hardness is what makes steel potentially dangerous for older guns.
Pattern and Penetration
Because steel pellets don’t deform, they naturally pattern tighter than lead at the same choke setting. A half-choke barrel shooting steel will often produce patterns equivalent to a full choke with lead, putting over 70% of pellets inside a 30-inch circle at 40 yards. For hunters, this means you generally need less choke constriction with steel to achieve the same pattern density.
Penetration results are more nuanced than many shooters expect. Testing by the British Association for Shooting and Conservation compared 32-gram loads of No. 5 lead and No. 3 steel at 40 yards. In bare ballistic gelatin, lead penetrated deeper: 82.8mm versus 67.4mm for steel. But when the gelatin was covered with pheasant breast skin and feathers (simulating an actual bird), steel actually penetrated about 4mm farther, averaging 52.0mm compared to lead’s 48.4mm. The likely explanation is that steel’s hardness helps it punch through the initial barrier of feathers and skin without deforming, while lead pellets flatten slightly on impact and lose some of their penetrating ability.
Muzzle velocities for comparable loads are similar. In the same testing, lead averaged 1,253 feet per second and steel averaged 1,240 feet per second. The real performance differences show up at longer ranges, where lead’s greater mass helps it resist air drag better, pellet for pellet.
Shotgun Compatibility
Steel shot’s hardness creates real risks for certain firearms. Older shotguns, particularly those made before steel shot became common, may have softer barrel steel or thinner walls that can’t handle rigid pellets bouncing down the bore. The most common form of damage is a ring bulge, a slight swelling in the barrel near the choke. In double-barrel shotguns (side-by-side or over-under designs), a bulge can spring the rib between the barrels or throw off the gun’s point of aim.
As a general rule, any single-barrel shotgun with a choke constriction tighter than modified should not shoot steel. Modified or more open chokes are typically safe in modern guns that are proofed for steel. If you’re shooting a vintage or heirloom gun, check with the manufacturer or a qualified gunsmith before running steel through it. Many newer shotguns are specifically marked as steel-shot compatible.
Environmental and Legal Differences
The shift toward steel shot was driven by one problem: lead poisoning in waterfowl. Birds feeding in shallow marshes and lakebeds ingest spent lead pellets, mistaking them for grit or seeds. Before the federal ban, an estimated 1.6 to 3.9 million waterfowl died from lead ingestion every year in the United States. The U.S. Fish and Wildlife Service, acting under the Migratory Bird Treaty Act, phased in restrictions starting with localized “hot spot” bans in the mid-1980s and completed a nationwide ban on lead shot for waterfowl hunting in 1991.
The results were significant. Lead ingestion rates in waterfowl dropped by 50% after the ban, saving an estimated 1.4 million ducks per year. Lead remains legal for upland bird hunting, target shooting, and other non-waterfowl uses in most U.S. states, though some states and several European countries have adopted broader restrictions. California, for instance, requires non-lead ammunition for all hunting on state wildlife areas.
Choosing Between the Two
For waterfowl hunting, you don’t have a choice: steel or another approved non-toxic material is required by federal law. For everything else, the decision comes down to what you’re shooting, what gun you’re using, and where you hunt.
Lead remains popular for upland hunting and clay target shooting because it patterns well at moderate distances, works in any choke constriction, and is compatible with virtually every shotgun ever made. Its higher density makes it effective at longer ranges without needing to increase pellet size.
Steel works well inside 40 yards, which covers most waterfowl and many upland scenarios. Its tighter patterning can actually be an advantage on close-flushing birds if you open up your choke. You’ll want to size up your shot (swap No. 6 lead for No. 4 steel, for example) to maintain comparable pellet energy. And if your shotgun is older or has tight fixed chokes, you should confirm it’s rated for steel before loading up.