When I got my first AR, that "sproing!" sound irritated the **** out of me, as I was used to mostly bolt rifles. So... I put in a pneumatic buffer. It worked great and then I started to get some doubling, or bump-fires, which I didn't like one bit. My gunmith, who's an AR guy from way back, said put the standard spring back in, as the buffer was altering the cyclic rate and probably causing the problem. Since I put the regular spring back in, no problems.

Don't think about messing with a good thing.... the "sproing" means it's working like it should!