Infinite Animation Loop for one thing while I animate other things? I made a character in Blender that is holding a Raygun.

The raygun currently has an animation from frame 0-5 where a light moves and blinks on and off. The Raygun animation is what I want to have loop forever while I make a walking animation for my character. 

I know I could simply duplicate the frames for the Raygun animation throughout the whole walking animation, but is there a more efficient way?

Thank you for any help!
PS: I'm using Blender 2.80 if that matters
In the graph view, add a cyclic modifier. That will repeat the animation indefinitely regardless of how many frames are in your final animation.