Acapulco faults the 3D printed gun he's using for his inability to hit two human-sized targets at almost point blank range. However, in his first scene, the Nurse tells him quite clearly that he only has "partial sight" due to his eye injury, and that a specialist would be needed to try to do any better than that. While a gun with such a short barrel isn't likely to win any accuracy prizes, the fact that Acapulco probably lost a good deal of his depth perception and parallax vision is probably the real cause for his poor accuracy.
