Upgrade: New XS Big Dot NS for my P40

[wyntrout]

Well, my Big Dots finally came in today... a day earlier than the estimate. I got them from Midway with a $1+ roundup and shipping for $114 total.

I ordered them 03-20-2013. They shipped 03-21 and I received them today, Monday, 03-25.

I was in the process of removing my old sights using my sightpusher.com Handgun Sight Tool that I got from the Glockstore.com when the new sights arrived by USPS. I had to remove the bottom block and use paperboard to get the slide at the right height to push the old sights out from left to right. The rear sight made a noticeable sound as it broke loose. The front just pushed slowly out.

The XS instructions say to use a non-marring punch(plastic one included), NOT a sight pusher for installation. The rear XS sight was a very loose fit, but it has two set screws and some thread blocker stuff is included to hold them in place.

I used alcohol pads to degrease the dovetails and dried them.

The front sights would not fit and I began sliding its base on a sheet of 320 grit sandpaper to remove material as the instructions say. I did this over and over and over... and I used my needle files to try to deburr the dovetail and the base of the FS. I put the slide in a vise with paperboard to protect it... the bottle separators from my latest case of wine yesterday. I used the non-marring punch and a hammer but could not get much past halfway into the dovetail. I tried more sanding and filing and again couldn't get any further. I looked at the FS from the side and saw that the front part that over hangs the dovetail still had a smidgen of clearance... the rear did NOT!
I figured this was where things were binding, so I undercut that a bit with a needle file... the front a bit, too. I blued everything... touching up with my Presto Bluing Pen... several times... and then was able to get the FS into position with the somewhat mangled non-marring punch and a hammer. The slide was in the vise for that.

Next I put the rear sight in place after putting some threadlocker in the dovetail. I slid the RS in place and centered it, then lightly tightened the set screws… did that several times until I was happy with the position. I tightened them snugly and added some more threadlocker around the RS and the dovetail.

I cleaned the excess threadlocker up and used a piece of the paperboard with a bit of Flitz to get the bit of bluing off the slide.

I checked the sights with my boresighter and they looked maybe an inch or less off to the right of the LASER's red dot, but I’ll see how it shoots first before adjusting them. The rear sights move easily and loosening the set screws should allow me to correct the position, if needed.
I have to start supper, so I’ll try to add a few pictures here… or a bunch. I took some measurements that I’ll have to annotate later. Wifey is hungry!

Wynn

[wyntrout]

First some measurements(before my removing material):
Base to top of notch: Kahr 0.161, XS 0.174
Base to top of Rear Sight: Kahr 0.250, XS 0.214
Width of base left side/right side: Kahr 0.293/0.294, XS 0.281/0.282(could be the same)

I guess I didn't do height above the slide, but I altered the underside of the FS overhang of the slide.

More Pix:

[wyntrout]

I focused on rear and then the front sights in the dark. I'm just holding the pistol in one hand and the camera in the other for quick pix.

And more pix:

[wyntrout]

And some sight pix. I'll have to add more info later... got to feed Wifey!

Wynn

[jocko]

nicework, if u cook asgood as u do gun work, well when do we eat???

[wyntrout]

I didn't have to "cook" tonight... just heat up the Costco chicken I got yesterday, and a can of corn and a can of Ranch Beans. I have two microwaves that I can use at the same time... full-sized ones... 1,250 and 1,000 watts with turntables. They come in handy and I could get my old one out and try to find a separate circuit for it, too.

Wynn

[gb6491]

Nice work Wynn (on both the sights and posts), thanks for taking the time to put it all together and sharing it with us.
Regards,
Greg

[wyntrout]

You're most welcome. A big thing that I discovered was the overhang on the FS being in the way after removing so much of the base's surface. It's a wonder that I didn't pop the front sight off the base!

I was really shocked at how loose the rear sight is... just plenty of room. I would have preferred a tight fit... not room to move fore and aft noticeably!

It's definitely something to watch on installations.

Wynn

[chrish]

Thanks a BOATLOAD for this Wynn. Been trying to decide whether to do this myself or send it off. [once I stop spending money on guns] Your post is easily the most thorough on the Kahr install of any I've read and it's making me think it's actually possible for someone w/ limited mechanical skills like me. Thinking of giving it a go.

Glad you said what you did on the sightpusher. I have one from SightPusher.com as well, directly from the guy that makes them. Would have used that and buggered the whole thing up likely.

The one part I don't quite follow is this...can you elaborate a bit, pict or drawing if possible. Did you take more material off the TOP of the FS at the front/rear edges, or from the bottom of the FS.

I looked at the FS from the side and saw that the front part that over hangs the dovetail still had a smidgen of clearance... the rear did NOT!
I figured this was where things were binding, so I undercut that a bit with a needle file... the front a bit, too.

[wyntrout]

I was surprised that the instructions said NOT to use the sight pusher, but it wasn't necessary on the rear, and on the front, I think that I would have broken the top part off the base by forcing it with the pusher. I don't have a brass punch, and the plastic one is tough, but got pretty battered with the force required as the top was binding on the slide. I used part of a UHF RF connector... the inner part fits over the RG6/59 that screws into the big outer part... as a punch to get the FS off after I aborted the first attempt. It's silver-plated brass or something like that... not steel, anyhow!

I need to break down and get some BRASS punches! Cheep!

Now I just need to see what Wifey needs on her G19. I think the big white dots will work for her. I can't wait to try the big dots at the range. I ordered a McFadden Ultimate Ultimate Clip Loader for my Ruger MK3 22/45 mags... holds 50 rounds and loads the mags in 3 seconds... $24 off Amazon Prime, delivered in two days. I would like to have that before I go to the range with the .22.




Wynn