Talk:Riven Mods/@comment-65.96.154.186-20161211010426/@comment-50.111.42.147-20161211011010

They only go on rifles, make sure you're not using a shot gun. If you have unlocked it already they're specifically for 1 weapon only that weapon is in the name of it usually something like "'name of weapon' acritio" or  "'name of weapon' puracron" or something similar.