Just posting this here for higher visibility than the Ammunition thread, but what the heck is 9x39 ammo? I've never heard of it, but apparently it's on sale at SGAmmo... I assume it's for a rifle? Kind of like a Russian .300 Blackout? But 9mm would be closer to .355 than .300.
https://www.sgammo.com/product/wolf...olf-subsonic-278-grain-fmj-bi-metal-case-ammo
https://www.sgammo.com/product/wolf...olf-subsonic-278-grain-fmj-bi-metal-case-ammo