Federal's Tungsten-Iron, with 94 percent of the density of lead, is loaded at high velocities and has excellent downrange energy. Because it requires a thick shot cup, however, each shell contains less shot, which limits its maximum effectiveness to the high-capacity shells. It's excellent for pass-shooting geese and open-water ducks. Use large shot (No. 2¿¿¿BBB) in magnum 10-gauge or 31/2-inch 12-gauge loads for best results. **Tungsten Matrix
Tungsten Matrix is the most like lead of all the approved nontoxics. A mix of tungsten and plastic polymer, it's 97 percent as dense as lead and even softer, which results in comparatively loose, long-range patterns. It's a good choice for close to midrange shots at ducks when hunting thick cover where quick, sure kills are needed to cut down on lost birds.