I like people try to close bolt with no round in mag. with out pushing down on follower 1st. they think its like there hunting rifle. they keep pushing and pull the bolt Then they say there's something wrong with it.
There are a lot of common errors people make when shooting military guns and I can't call them stupid because we were all newbies once.
The one I get asked a lot is why does my SKS only fire single shot?
First thing I ask is - Is it a Yugo? Then if they answer yes I tell them make sure the gas valve isn't in the closed position.
The only thing I can honestly say is stupid is when someone buys a surplus gun and hits the range with a box of ammo w/out disassembling, cleaning, and inspecting it first and doing some research on how the gun functions. I've read countless threads on people asking why a rifle did this or that only to find out after taking it apart for the first time an extractor, firing pin, etc. was broke or it was gummed up full of cosmolene.