John loses H2H, but should win with a gun. Elektra did deflect a bullet with her sword, but that guy had nowhere near the gun feats that Wick does, so won't have Wick's training, hand speed, co-ordination, or tactical knowledge (in terms of trying to spot weaknesses etc.). Dealing with a panicked, in-experienced gunman is not the same as dealing with a hardened killer like him.