Recently, when shooting at 500 yards with my Millett TRS-1 4-16X atop my rem 700 .308, I noticed the rounds impacting 2.5 MOA low on a recent shoot. I’ve shot at this distance and greater several times and my data from JBM has always been dead on as far as elevation is concerned. I dialed back to my 100 yard zero and shot several rounds at 100 yards to check for a tracking issue. No issues here. The scope returned to zero almost perfectly. How did I lose 2.5 MOA in adjustment at 500 yards in just a couple weeks? Same Ammo, nearly identical weather conditions. I’m not familiar with the internal workings of the scope or how the elevation turret works. I’m hearing definitive click when I rotate the turret although it has always been a little mushy. Any ideas?