I have read the manual and can't find anything on this. How do you loot a corpse? I hit the A button but instead of getting what ever is on the corpse or getting the weapon on the ground, I end up "grabbing" the corpse or weapon. So how do you loot a corpse or get that weapon that is on the gournd so I can use it?

Tap A to loot or pickup things. Hold A to grab.
If doesnt work maybe your A button is sticking

Just tap A dont hold A.

to get dead enemy weapons you press a on weapon or if that doesnt work press a on the corpse and select the weapon from their inventory.

Thanks guys, I was tapping the A not holding it. I tried another controller and it seems to be working now.

Guess maybe my other controller the A is sticking then. Doesn't seem it is sticking. But thanks guys, this helps me play the game so much better now.