I love my MC but I dont think its unusual for POI to change with different loads. Shooting 160gr RNFP with H110 and magnum brass in my gun always shoots high left but when i go down to 130gr RN in 38S brass is spot on so i dont bother adjusting the sights. I shoot mostly 38S and medium load 357s and only few full magnum loads so I'm fine with that.