If you aren't using IK in game, then you need to animate the reloading animation with your gun inside you animation software, and then export this to the game engine. Orient the gun rotation inside the game is engine specific and there is a lot of way to do this. The most common for objects that attach to character is…
My character starts out without a gun (its survival) but finds guns later in the game. I want to have the gun holstered first then taken out, which then leads to the reload and fire animations. I know you can do the firing in IK if you wanted to but what about the reload with the clip? The problem is that I don't know…