I have a new DB15 .556 16" that is throwing brass at the 1:00-1:30 direction. The gun runs very well, no lock back issues, no brass rim damage, no misfires, etc. I'd like to change out the original buffer spring and/or weight before trying anything else. My question is: can I use an H2 or H3 weight with the original spring, or should I use a heavier spring with the original weight? Which adjustment should I try first? I appreciate any info. Thanks!