At the moment my Char has 2 primary Weapons, a Mosin (black/1 round^^) and a sawed off shotgun.
One on my Char's Back one in his hands. When i want to change the weapon in hands, i need to lay both down, put one on my shoulder and grab the other one with the "F" button..
Today i found out, that i cannot grab a weapon with "F" when i've dropped it sitting in a fir or like 2-4 meters next to it.
It depends on the position of the dropped weapon, not the position of the player!

Almost gave me a heart attack today with enemys 200 meters in front of me and a shotgun in my hands.. :D