i have found that in other calibers that heavier bullets hit higher at reasonable handgun distances due to "hang time", also faster ones due to a flatter trajectory. but i have yet to see it affect windage to any degree, just elevation. but i'm casting some 255 grainers. will see.Try a heavier in the vaquero. I have an uberti that shoots right with a 200gn bullet. I went to 250gn bullets and now it shoots right on.