There is a rendering sort priority I THINK but that’s a C++ thing, the best way to avoid weapon clipping through geometry (IMO) is to use an overlap collision on the weapon and enable the player character to ‘move’ the weapon out of the geometry via animation. Gears of War did this for each game in the series I believe, though I’m yet to see an example of it set up in UE4.
In fact, this would be a great C++ Animation tutorial (hint hint epic games). I believe it’s done with blends and IK’s