Since the latest update the Silver Pigeon and Izh43's aiming crosshairs have been changed when you're standing, crouching, or prone. Standing is most accurate and gets less accurate as you are crouched or prone. I don't know if this is a glitch or was meant to be this way, but it doesn't make any sense to me.
Also it seems the damage output of the Izh43 has been turned down. It takes about 4 shotgun shells to the chest to kill now. At least that's how much it takes to kill scarecrows.