So i just found a duplication glitch by having bad server connection . So to do this glitch you have to time it perfectly. First of all you need bad server connection, thats beeing in a server while it has a bad or slow server. Then you need to wait and have the item in your hand for the server restart and 10 seconds before server restart you place the object in a Crate or Barrel and wait. After restart rejoin as fast as possible and as expected you should have the item in your hand and in the Barrel. Then you might think it didn't work because you cant drop the item in your hand but then you have to exit the game and rejoin and now you have of the exact item.