Had this happen this year. My 28 nosler shoots high with clean bore at 500. Settles down after that one shot though. Got dirt and dust in the action and had to clean it before the next hunt (didn't want galled lugs or worse in the bore). Cleaned it real good at home. Next day, Bored waiting for elk, I couldn't help myself and whacked a rock at 796. It was a couple inches high like normal. Just know what it will do and you'll be fine.Speaking of hunting, here is my reasoning for shooting a clean bore 1st shot. What if you have to clean your rifle? *Rule 4 Violation* happens, people plug barrels with mud every year. Branches get scraped, grass is crawled through, birds poop.... or whatever reason. I know I can consistently get my bore clean the same way every time. And, it just so happens my shots are repeatable. Maybe I got lucky with this rig.