I think something else might be going on here. If your rear sight is skewed right, then your groupings would skew left.

Here’s an image that kind of depicts what I’m referring to: https://www.google.com/search?q=zeroing+aim+left+and+right&tbm=isch&ved=2ahUKEwj7tILGpJvrAhXBG98KHQ16CykQ2-cCegQIABAC&oq=zeroing+aim+left+and+right&gs_lcp=ChJtb2JpbGUtZ3dzLXdpei1pbWcQAzIFCCEQqwIyBQghEKsCMgUIIRCrAjoECB4QClD4MljwVGCmWGgAcAB4AIABcYgBqwqSAQQxMy4ymAEAoAEBwAEB&sclient=mobile-gws-wiz-img&ei=ttI2X_uBPMG3_AaN9K3IAg&bih=553&biw=375&prmd=ivn&rlz=1CDGOYI_enUS780US780&hl=en-US#imgrc=Shn2vg26Bim2NM

Is it possible that it’s a trigger finger issue? Such as; if you’re right handed, your finger is too far past center (too close to the first joint), or if you left hand shooting then not enough of your finger is across the trigger?

Here’s a helpful chart for identifying trigger squeeze issues: https://www.google.com/search?q=trigger+pull+chart&rlz=1CDGOYI_enUS780US780&hl=en-US&prmd=isvn&source=lnms&tbm=isch&sa=X&ved=2ahUKEwj1vcGYppvrAhWLslkKHdDbAgkQ_AUoAXoECA4QAQ&biw=375&bih=553#imgrc=CJxxXESowZT9_M