S&W Rear Sight Problem

Ganderite

Ganderite

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I have adjusted the rear sight on my M18 as far right as it will go, but it is not quite far enough.

I have quite a few S&W revolvers with adjustable sights and have never had a problem before.

I bought this 22 used. Is it possible to remove the rear blade and re-install it backwards? Is the blade symmetrical, or is intended to go in only one way?

I know I could remove it myself and take a look, but I have had bad experiences removing spring loaded small bits. Most went SPROING! and were never seen again.

Anyone got a picture of what a rear blade looks like, removed? I am thinking the underside notches might be different. One for the spring and one for the screw.
 
I have changed/replaced three different rear sight blades. One on a 17-3, one on a 19-3 and one on a TRR8.

On the TRR8 I changed out the v notch for a square notch.

The underside of the blades are identical on each side. Sorry.

And yes, they are a b*tch to replace. Tiny bits and springs.
 
Something else might be haywire if you need to adjust it that far off center. . .

They're quite straight forward to remove and replace. . Start by removing the rear site assembly from the top of the frame. . Two screws, but use a proper screw driver and be careful you don't let the screw driver slip off the screw head and leave a reminder on your gun. . Once the site assy is off the gun; do what you need to do but pay attention to how things are and hold everything with your fingers as you're taking it down. That way stuff won't go flying around the room.
 
Find someone with a "range rod" these are used to check alignment of cylinder chambers and barrel but they also serve to check that the barrel is straight on the frame. Of course the sights might just be bent. But check out the alignments too.
 
NONE of my S&W's need to be that far out. I'd have the frame and barrel checked for straightness. Or since it's that far out you can do it yourself. Flip the cylinder out and lay a ruler along the frame. Measure from the ruler to the barrel. But likely just by laying the ruler along the side of the frame next to the barrel you'll see the issue.
 
1835wahulue8tjpg.jpg
 
Ganderite said:
Anyone got a picture of what a rear blade looks like, removed? I am thinking the underside notches might be different. One for the spring and one for the screw.
Click to expand...

Here you go:

DSC_0099_zpsfjntcktm.jpg


The blade should be reversible (except a white outline version like I have shown will lose that feature). There are no notches on the blade; the click adjustment is found on the head of the screw going across the sight, a hole to accept a tiny spring and plunger.

I wouldn't call it *easy* to change the blade. First off, the screw is a sacrificial part, so get a new one first (nine greenback dollars at Brownells I recall). Remove by shearing the head at the end of its travel, then pliers on the shaft and run out. You need to clean all threads so it doesn't bind and break during your install! Run blade to the middle of the screw, fit in sight body with plunger and spring, and install fiddly tiny spanner nut. Stake screw over nut with a centre punch.

Maybe if the screw was staked with the blade un-centred, this caused the off kilter aiming?

Filing the notch seems like a quicker solution.
 
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