I installed a white outline rear sight blade on my 686. Just chrcked sights with a laser bore sighter and.I.had to crank the tear sight all the way up yo get them to aline. Do.I need a taller rear blade?

Kuhnhausen's shop manual, page113, calls for a .146" for a 4" 686, and .160" for a 6" 686.

Where the bullet hits in relation to the sight picture is not always a straight line. Distance, speed, bullet weight, etc play a part. The lazer sighter may get you on paper.

No, laser bore sighters work OK for rifles, but not at all well with revolvers. A revolver needs to point the bore line well below the line of sight as the revolver recoils while the bullet is still in the barrel raises the bore to roughly where the line if sight was with the gun static. Try actually shooting the gun and adjust the sights accordingly! Bore sighters simply don't work with handguns!

Next time check alignment of a gun that shoots to the sights before making any changes and you will see what I mean!!!

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Gunsmithing since 1961