I had (have) a similar experience, but with slower bullets.
My .38/.357 lever gun shoots higher with 125gr .38 Spl. than with 158gr .357 Magnum.
The .38 Spl. rounds are lighter and a lot slower and have a lot less recoil, but hit higher.
It’s an 18” barrel, not a 4-1/2”, so it’s not a...