Classic lead ammunition is increasingly being replaced by lead-free ammunition. Hunters are at best critically aware of this transformation, which is justified by widespread lead bans, as lead-free shot brings ballistic disadvantages:

On the one hand, the flight characteristics of steel shot are worse than those of lead shot. Lead shot can be fired further if necessary, as they deliver more energy to the target. With steel shot, a maximum distance of about 30 meters must be maintained. The fact that lead shot delivers more energy to the target should also be considered when choosing the shot size: With lead-free ammunition, the shot size should be slightly larger than with lead shot. 

Another disadvantage of steel shot is that it can be deflected more easily. When shooting at hard surfaces or water from a shallow angle, there is a greater risk of ricochets with lead-free shot. This is also criticized by hunters regarding lead-free rifle ammunition, as it significantly increases the danger zone.

To fire lead-free shot from shotguns, they must be proofed for steel shot. This follows from the following properties that steel or soft iron brings with it: 

Steel shot is significantly harder than lead, with a lower specific density

This brings the following consequences in addition to those already mentioned:

• With the same load and grain size, more individual shot pellets
• higher penetration power despite lower impact energy
• faster loss of speed of the shot cloud
• Individual shot pellets do not deform in the barrel anymore because they are too hard. Because steel shot does not give way, the stress on the barrel increases, and individual shot pellets are pushed sideways - risk of "edge shot pellets"
• Lower killing effect when hunting - The shot pellets penetrate deeper into the game body but release less shock energy.

This leads to the following for the ammunition:

To achieve the same performance as a lead-containing cartridge, lead-free shot ammunition must be loaded more heavily. To prevent the barrel from being stressed by the hard shot pellets, other intermediate materials must be incorporated into the cartridges to prevent contact. The steel shot proofing (visible on the barrel as a "lily") indicates that the weapon is capable of withstanding the higher stress.