pass the reticle tru, and hold the fluff......
This ^^^^^
The Reticle-Tru is far more effective than any of the devices using a bubble, or that assume any flat part of a scope is actually square to the reticle, or requires the rifle to be level. Instead, it aligns the reticle with the center of the rifle's action.
That said, a LOT of shooters see any reticle as being "crooked" because they don't hold rifles level. I have known quite a few shooters who consistently mount scopes at a certain angle, because the scopes then appear level to them when aiming. One of these was a very experienced hunter and competitive shooter, who knew exactly what he was doing. Another, however, did not--until he actually looked through a perfectly squared scope on another person's rifle, and declared it was "crooked."
Saw this again in a local gun shop just yesterday. A guy had brought a new rifle and scope to the shop's gunsmithing department to have the scope mounted, and came in to pick it up. When he shouldered the rifle and looked through the scope, he declared it was crooked. However, his son (who looked to be in his late teens) also shouldered the rifle and said it looked level to him. The difference was the father was pretty "stout,"and the son was not. Consequently the father's stout shoulder tended to tilt the rifle when he aimed through the scope. I could even see this plainly from across the room.
The gunsmith had seen this many times, but instead of trying to tell the father he was FOS, said: "It's your rifle, and you're going to be shooting it. I'm happy to make it feel right for you." Which of course involved mounting the scope "crooked."
