5.7x28mm AP is an unused ammo type which was partially included in S.T.A.L.K.E.R.: Shadow of Chernobyl.
Characteristics
Usage
No weapons implemented in any S.T.A.L.K.E.R. games or accept this ammunition. However, it can be assumed that the unimplemented FN P90 would have used this ammunition, since no other weapon has this caliber.
Appearances
Build 1935
5.7x28mm AP rounds are present in Build 1935's resources, complete with inventory icons and an in-game model. However, the ammunition is not carried by any Stalkers and is not available for trade.
Shadow of Chernobyl
Unlike Build 1935, Shadow of Chernobyl does not include inventory icons for this ammunition. The in-game model remains present and the ammunition is still implemented within the game's code. Curiously, the ammunition appears to have stats identical to those of 5.56x45mm AP ammunition.