There's a crows nest/sniper tower in the wooded outskirts (north-east i think) of zelenogursk. I climbed up in it, crouched down, then stood up and fell out of it to my death.
So f'ing frustrating spent all day playing, had an sks with a scope, ton of food, character was healthy...yadda yadda...sigh. Really wish these building glitches could be addressed.