9х42mm FMj ammo

Can be used to fire this weapons

M82 Aperture rifle M82 Aperture rifle
KF866/9R Mehrzel Repeater KF866/9R Mehrzel Repeater
M1866/9 Einzel Breechloader M1866/9 Einzel Breechloader
M82 Rifle M82 Rifle

Where can you find it?

Rare weapon crate Rare weapon crate