i have a new (to me) 15-3 that has half of the rear sight blade broken off. How hard is it to replace? are the parts readily available?

You'll need a new blade, screw and lock nut. The set costs about $11 from S&W, Brownells, or Midway. There is a tiny (repeat tiny) spring and plunger that fits in a hole in the screw head and rides inside an hexagonal socket.

You can download instructions from Brownells or the internet, or find them in any basic book on gunsmithing. You can notch a screwdriver to span the lock nut, or just break the screw by turning it to the right. To finish, stake nut to the end of the screw with a center punch.

It's a 2 minute job, unless you spend an hour looking for that little spring.

I looked out at midway and they have a "kit." It comes in several sizes. Any idea which size blade i need for the 2 inch barrel?

Yes sir, watch out for that darn little spring and plunger. I am ashamed to admit to the hours I spent looking for them.
What I now do, is call the federal government weapons sight replacement response team prior to any attempt. Of course I pay the
$10.000 fee that comes along with them. I KID........................

Throw a rag over the weapon prior to removing the sight blade and screw to catch the tiny parts that may fly away.

My solution is a large clear plastic bag, such as a food storage bag. Put the entire gun in the bag and both hands, so when the TINY spring and detente plunger go flying they will be captured. There is still a set "somewhere" in my workshop from my first blade change.

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H Richard
SWCA1967 SWHF244

I have found the rear sight kits, so my question now is, which one do I need for the 2 inch 15-3?

.126, .146, .160

And what is the difference? Thanks!

Do you have a dial caliper or 1" micrometer? Turn the windage screw all the way, either way, and measure the height of the end of the sight blade that is hanging out the side of the sight. Just that simple. If all you have is a 6" machinists steel scale, then the .126 will be 1/8", the .160" will 5/32", and the .146" in between.

If you order the sight kit from S&W it comes with an instruction sheet. Be sure that when you turn the windage screw to break off the screw head that you turn it clockwise, (to the RIGHT). Both Midway's instructional CD and Kuhnhausen's book say left, they are both wrong. The S&W instruction sheet gives you the correct information, they ought to know, they made it!

When you order the sight kit, order 2 each of the sight plunger and spring, for the small amount they cost it is good insurance against the frustration when you lose the ones in the gun. I have also had several that you cannot get out of the screw head, no one seems to ever mention that.

Finally, if measuring the blade height is beyond the limits of your mechanical ability, or you don't know clockwise from counter-clockwise, let someone do it for you that does possess these attributes.

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Gunsmithing since 1961

And that my friends is the voice of experience! I did a spit take when I read that...

You need a 0.146" blade, according to Ham Bowen.

+ Bowen Classic Arms + Parts Store

Buck

Thanks to all who have responded. I have ordered the partts from S&W, all were in stock except for the plunger springs which should be avaialbe in a few days. Will post when I revieve and let you know how the install works out.

Since the rear sight blade is broken you could unscrew that sight adj screw and get the plunger and spring from your old sight and either use them or at least have a spare. Good luck, Bob

Got the sigt kit in today and installed in about 10 minutes. Did drop the plunger once but found it. Looks like new. Thanks to all for their input!