After 1000 rounds, I've found that it should be a bit tighter than the directions say it should be. Make it tight, then go an extra one and tighten and it'll hold. And that's with 5.45 so I imagine with 7.62 it'll be apparent much earlier. I mounted a Vortex Crossfire to it and I love it. The combo is small, light, tough and reliable, but it took a little bit to get that tightened just right. Not complaining, just advising.