UE4 Automatic weapon gunfire

I’m designing the audio for a load of weapons in the Squad Dev Kit at the moment, though i’m having an issue. My problem is whenever i try and make a loop for automatic fire using SDK’s ‘fully auto loop’ the loop just ends up sounding like the same sample played over and over again (robotic.) The auto loop node in the sound cue basically lets you select a start and finish sample, so trigger and tail, and in the middle, for the duration of the mouse press, plays a loop from a number of samples you have chosen. I am aware that to create an organic, living automatic gun sound, every sample needs to be slightly unique in pitch and velocity.

Though, im having trouble giving each sample different pitch and velocity in my DAW to cause a noticeable difference in-engine. Does anyone have any experience with designing weapon audio and in particular, very short samples for use in a loop sytem?