Why the laser won't give true accuracy results. The laser down the barrel will give you point of aim in relationship to the barrel / sights. The actual bore size and quality of rifling will determine accuracy as well the quality of the crown. You can have a revolver that passes the laser test, that will fail miserably in the accuracy dept. The laser is an OK start, but not the true determination of accuracy. The laser would would show ok on a worn out smooth barrel with a chip taken out of the crown.