Note: your point of impact will undoubtedly shift when switching from heavy RN to light and fast SWC's. Does your gun have adjustable sights? My .45 platform is a 1913-vintage government issue M1911 (refurbished in WWII at Rock Island Arsenal), complete with the early "no see-um" sights. The sights are regulated for hardball ammo and as such they work to shoot true with 230 RN cast loads driven at hardball velocity, but when jockeying bullet styles/weights/velocities I have to employ "Kentucky windage and elevation". (And no, I have no intention of altering the old girl at this point in her life with better sights. She is what she is, and I love her warts and all!)
