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"Lead-free, non-toxic ammunition, tested and adhering to all local and overseas hunting restrictions. Especially designed for effectiveness against small bird species.

Bird shot contains a huge amount of small pellets. This gives it short effective range and low damage. However, the wide and dense pattern generated by these properties also makes it ideal for hitting small fast-moving targets such as small game and birds.
― In-Game Description

The 20 GA Steel Birdshot is an ammunition type available for the Strecker SxS 20G and Nordin 20SA families of shotguns.

This ammo is available as part of the Wild Goose Chase Gear and Duck and Cover Pack DLCs.