XS sights for CM series

[68Firebird]

I have been wanting upgraded sights for my CM9 ever since I put TruGlo TFX Pro sights on my FNX-9. TruGlo doesn't offer those for the CM9 (I inquired and got a nice response, but no promises) so I researched XS DXT "Big Dots." Their web site says they offer sights for the CT/CW/CM series, but only with factory installation.

Since I live near their Fort Worth location I sent an email asking if I could just bring my gun and have an opportunity to see the different styles they offer first hand.

I was surprised to receive this response: We no longer offer the screw on version. Its long term durability is not what we want.

We don’t get to choose how the gunmakers decide they are going to install their sight but the twin little rivet holes that hold that plastic factory front just are not big enough.

[Ed M]

Sounds a bit harsh, but I gotta agree with XS on this one.

I just put the Trijicon night sight set from Kahr on my CM9 about a month ago.

Yesterday at the range, the front sight went AWOL. I found the sight in the grass, but the post that the screw goes into had broken off the sight at the base. I wasn't able to find the broken post and screw.

I used red Loctite on the screw, and was careful not to over-tighten it when I installed it.

Called Kahr, and they're sending me a new sight - and TWO screws. Seems they've experienced this breakage problem before, and their new CM Trijicon front sights have BOTH posts threaded, and they now come with 2 screws. They feel it is more secure to have the sight held on by two screws.

Sure hope this eliminates the problem, as I'm sure I didn't damage the sight on installation or after it was mounted.

[gb6491]

Sounds a bit harsh, but I gotta agree with XS on this one.

I just put the Trijicon night sight set from Kahr on my CM9 about a month ago.

Yesterday at the range, the front sight went AWOL. I found the sight in the grass, but the post that the screw goes into had broken off the sight at the base. I wasn't able to find the broken post and screw.

I used red Loctite on the screw, and was careful not to over-tighten it when I installed it.

Called Kahr, and they're sending me a new sight - and TWO screws. Seems they've experienced this breakage problem before, and their new CM Trijicon front sights have BOTH posts threaded, and they now come with 2 screws. They feel it is more secure to have the sight held on by two screws.

Sure hope this eliminates the problem, as I'm sure I didn't damage the sight on installation or after it was mounted.

FWIW, something I found with the Trijicon front sight was that the legs flare a bit where they meet the sight body. This made the sight sit proud of the slide when checking the fit. I was concerned that tightening the screw enough to make the sight sit flush might stress/damage the sight leg. I countersunk the holes on the top side of the slide just enough that the sight would sit flush when pressed into place. I also filed the back leg short enough that it was just below the surface of the underside countersink and I also shortened the screw. The only proof I have that that the preceding had any effect is that I've not had a Trijicon front sight come off any of the three Kahrs I have them on....or maybe I'm just lucky that way
http://www.kahrtalk.com/showthread.p...962#post384962

Seeing as how there are variances in how slides are countersunk for the front sight posts on "C" (and "E") series guns, I thought I'd put up some diagrams in regards to what I've found is involved with "fitting" the Trijicon front night sight. YMMV.
First, do a dry run installation.
Check that the sight will fit flush on the slide. Then check the posts for correct clearance on the inside of the slide. Finally, install the screw and check that it holds the sight flush to the slide and fits correctly into the countersink.


*note - in the diagrams, fit of the sight posts in their holes and screw head in the countersink are exaggerated to show the parts clearly. The posts fit closely in real life and the screw head will be in contact with the sides/bottom of the countersink.

Once satisfied that the fit is correct, install using an adequate amount of red Loctite.
...

Regards,
Greg

[Ed M]

Wow - that's some serious attention to detail!

I just checked the remaining post on my broken sight, and it's not flared where it meets the sight body. Perhaps Kahr/Trijicon tried to remedy that problem and created another one (making the post weaker). The post is proportionally shorter than in your diagram as well - looks like your filed back leg when I hold it on the slide.

I like your solution better than Kahr's. Hopefully the 2 screw solution does the trick, but you can bet I'll be checking those post bases for flaring when it gets here.

Thanks Greg - you are the best!

[68Firebird]

Nice work, Greg, as usual.

I'm no engineer, but I would think XS Sights' concern could be addressed by enlarging the holes and using larger screws in both posts, similar to Kahr's approach.

Would it be reasonable to guess Kahr has gone to the two-screw design on all the front night sights they're shipping now?

[Ed M]

Would it be reasonable to guess Kahr has gone to the two-screw design on all the front night sights they're shipping now?

That is exactly what the girl I spoke to on the phone told me Kahr is doing. Both posts are now threaded, and two screws are now included - at least on this sight:

http://www.kahr.com/Sights/Kahr-CTCW...T-KWTFNSKT.asp

FWIW, I had no idea they were doing this until the sales girl told me about it. With a proper length post and matching screw setup, maybe this would work for XS as well. With as good and unique of a product as they make, it might be worth their time to revisit their decision. If you're really wanting a big dot setup for your CM9, maybe another email to XS informing them of Kahr's solution is in order. They may be unaware...

[bugs]

I had a dovetail milled in the CM9 slide so I could use Tru Glo TFOs, grn.ft./yel.rear; my 70 yr. eyes like TFOs best, but I can use any sights w/dovetails if I want. best choice I've made in a long time!

NRA LIFER
IDPA BELEIVER

[Joe in Frankfort]

Thanks, Bugs...just what I was wondering. I just sold my 3" SP101 because my 69 year old eyes can't cope with stainless on stainless substitutes for sights. I thought about having the rear dovetailed for a Kahr 380 sight. Ruger should have done better.....

[Joe in Frankfort]

Who did the work, if I might ask?

[bugs]

I had a LGS do the work for me; I bought the CM new @$369,add about $80 for the dovetail, total is still less then what I could find a PM for and TFOs would still have been bought for the PM.
this is my EDC/Competition gun so during carry w/o shooting glasses, sights grn./yel. are bright enough to be easily seen; w/shooting glasses f./r. are sharp but I focus on grn. front dot. TFOs moved me from MM to SS, IDPA BUG. it works for me.

NRA LIFER
IDPA BELEIVER