I recently purchased a few of Forge World's renegade ogryn.
They are great models very brutal looking.
The problem is none of them are modeled with a Ripper-gun they all have only CC weapons.
To remedy this I used the GW Bone 'Ed and converted him to match Forge Worlds stuff.
I used green stuff,plastic tube and rod along with DragonForge's pewter cabling to make the
conversion,along with the Redeemer's inferno cannon fuel tanks for his backpack.