I just picked up a lightly used 459, blued. Functions perfectly except the sight blade slops side to side. From buggering on the winfdage screw I suspect some prior owner tried to do something and lost a spring or plunger. So, I ordered a replacement sight assembly from Numrich/Gun Parts and set out to learn how it attaches to the slide, preferably without doing any greater damage. So,
How does it attach to the slide? Do I remove the elevation screw and find the secret under that? If so, what springs are going to fly how far?
Pictures or, saying a short prayer, u-tube video would be a great help?
Thanks

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Is this the kind with the wings on either side?

Scroll down in this link...

639 rear adjustable sight disassembly

I think so. A ramp lies between two sloping walls.

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Thanks jmace57. That looks like the one I’m facing. But holy cow, could they have put just one more booby trap in it?! I’ll get out my 2 gal baggie this weekend and see what I can learn. Will report back.
Dave

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It’s been a while since I disassemble one, but seems like you remove the elevation screw completely and pivot the sight body forward toward the muzzle. Doing so will reveal a screw that holds the winged base.

Yes, that is the adj rear sight on a 2nd gen. I have one on a 439.

Lets see if this helps a bit...
you'll need a little punch or some pointy tool to depress the plungers on the sides.


What you want to do here is pull rearward on the blade gently and depress the plungers one at a time until both are released from their holes and the whole elevator assembly slides rearward a touch.


Don't worry about the front/center plunger, there's no spring tension there once you slip the elevator back a touch.

Now you want the pinch the area where the side plunger are between thumb & forefinger as you gently lift the elevator up and out of the guard, like so...


Once you have the elevator out in hand just ease off the pinch and set it down. Taking the thing out is easy...There's a much greater chance of losing stuff when you put it back in.


With the elevator off there's a little socket head screw under there fixing the guard in place.


The guard can be driven off to the right with something non-marring and a small hammer. I use a chunk of 1 inch delrin rod.

Bear in mind there's two more springs under that guard for the firing pin safety plunger and the ejector depressor plunger.

Cheers
Bill

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Because they don't make a .46

Sliding the sight rearward to remove the spring tension on the front plunger was a LOT smarter than the way I did it!

Jim

Thanks a ton, Bill. That helps enormously. I had about decided to drive out the "pin" that holds the elevator in place, but learning that it is a pair of spring-loaded plungers may save me a hands-and-knees search later in the process.
Dave

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Thanks, Bill. Went. Slick as a whistle. I found that a couple of very thin feeler gauges made fitting those side pins back in fairly simple.

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I imagined it I suppose, but I thought somebody made an insert with a small dovetail that replaced the monster rear sight, basically filling the huge slide cut with a blank that fit 2nd gen fixed sights. Anyone know what I am talking about?