CM9 recoil guide rod cap missing

[cleatusvandamme]

Hello,

I am new to the forum and a new owner of a CM9. Got it Saturday and was able to go shoot it yesterday. It performed flawlessly through 250 rounds of various different grains and bullet types. When I got back up to my house I was going to field strip and clean the gun and mags. I racked the slide back and engaged the slide stop to ensure the gun was empty, but before returning it to battery I noticed exposed threads on the end of the guide rod. The end cap had backed off sometime during the firing cycle and could not be found in the thick grass of my field. I called Kahr Technical support and they are sending me the whole assembly. Wish I could find an end cap for the one I have so I would have an extra recoil assembly. They told me that the CM9 uses the same recoil assembly as the PM40 since it is closer in dimensions to it than the PM9.

[jocko]

Hello,

I am new to the forum and a new owner of a CM9. Got it Saturday and was able to go shoot it yesterday. It performed flawlessly through 250 rounds of various different grains and bullet types. When I got back up to my house I was going to field strip and clean the gun and mags. I racked the slide back and engaged the slide stop to ensure the gun was empty, but before returning it to battery I noticed exposed threads on the end of the guide rod. The end cap had backed off sometime during the firing cycle and could not be found in the thick grass of my field. I called Kahr Technical support and they are sending me the whole assembly. Wish I could find an end cap for the one I have so I would have an extra recoil assembly. They told me that the CM9 uses the same recoil assembly as the PM40 since it is closer in dimensions to it than the PM9.

that is totally untrue. the pM9 and PM40 use the same exact guide rod and recoil springs. wow I wonder where they come up with this sh-t!!!

[cleatusvandamme]

So does Kahr sell any separate parts for their recoil assembly? I couldn't get much out of them about it, but they gave no hassle about sending me the new assembly.

[jocko]

no u have to buy the complete set up at $24 plus postage. I thinik Wolffs will eventually come out with a replacement outter spring as thatis all u need to reall;y replace andnow with the new assembly, u have two outter springs, so u should be good to go for a very long time of shooting, at least 5000 rounds...

[cleatusvandamme]

Thanks Jocko,

I am thinking about loosening the end cap on the new one and applying some loctite to it so it does not come loose again

[Bawanna]

Thanks Jocko,

I am thinking about loosening the end cap on the new one and applying some loctite to it so it does not come loose again

The downfall to that plan is if it was installed correctly and loctited you'll crack it loose and perhaps make it come loose even more.
My PM45 has basically the same setup and after reading of this happening I just check it once in awhile. In between mags at the range with the gun locked open I'll just grab it with my fingers to make sure it's not moving. You should also be able to see the rod backing out of the end cap as it won't be flush.
That cap is a real bugger I'm told to replace, trying to get the spring compressed and getting it threaded could be a challenge.
As you discovered the gun will generally continue to run even with the cap gone so while it's not cool to have one that flies off, its also not a game stopper.

[wyntrout]

They don't sell just the nut, but you can make your own:

http://kahrtalk.com/showthread.php?t=3934

I wouldn't advise breaking the nut loose so YOU can Loctite it. Don't fix it if it ain't broke!

Wynn:)

[TucsonMTB]

Green Loctite 290 (http://www.matweb.com/search/datasheettext.aspx?matguid=8f339ffeab324718a09119f 81683d67e) is described on the little tube I have as being a wicking grade capable of securing parts that are already assembled.

I have used it many times with items that were already assembled and it seems to work like medium strength Loctite. :)

[mr surveyor]

I think I'll look a little closer at the construction of the CM9 now before I make the purchase for a new wonder nine. I had no idea this was a potential issue:(

[TucsonMTB]

Hey Surv!

I believe you will discover that the recoil assembly is the same as the PM series and the frequency of loose nuts is vanishingly small.

Still, there are lots of 9mm pocket toys out there, so take your time. :)

[wyntrout]

Green Loctite 290 (http://www.matweb.com/search/datasheettext.aspx?matguid=8f339ffeab324718a09119f 81683d67e) is described on the little tube I have as being a wicking grade capable of securing parts that are already assembled.

I have used it many times with items that were already assembled and it seems to work like medium strength Loctite. :)

I compared the technical data on both thinking that the Permatex Green was equivalent to Loctite Green. Both are wicking grade, but the Permatex is probably at least twice as strong, depending on how you compare them. It takes something like twice the torque or more to overcome the Permatex. If you follow the directions and clean the threads on the hole and the screw, you can get a very strong bond. It IS applied after the union and wicks quickly, making a good seal and bond.

I think too many people just grab the strongest...the Red. That is rated PERMANENT, being a kind of SuperGlue-type bond. That NOT something to be used on small screws that may need loosening. The nut on the end of the recoil spring assembly is definitely a candidate for that permanent bond. Kahr considers it so, though like everything, stuff can fail.

The torque and heat requirements to break most of the bonds exceeds the strength of the material, especially plastic/polymer.

Loctite should NOT be used on plastic or polymer as the bond is stronger than the plastic, almost guaranteeing the polymer will fail when you try to remove it.

I'm not preaching to the choir but trying to keep some of this stuff out for everyone to see. Not everyone reads the danged instructions... or follows them.

Wynn:)

[jocko]

that green locktite, IMO is to strong for that end cap. go with the red, if u ever intend to try to take it off, if not IMO the green is better, it penetrats.. I have used both the red and green and I find the green a real bit-h to get off, especially if it is used on a small threaded peace. I think it is used more successfully on bigger bolts, where excess torque can break it loose...

If u get the end cap and treads clean, the red is more than enough. IMO

[RogerP9fan]

Thanks for making us aware of this issue.
CM9's gotta be the best 9mm pocket toy out there, I'd think. lol

[cleatusvandamme]

Thanks for all the input, I will try the green loctite. Yeah I wasn't really wanting to take the new one apart and had decided not to. The gun runs just fine, very pleased and impressed with it overall, just a minor setback. I also want to note that it runs great with the 7 and 8rd magazines that I bought for it, had heard that was an issue for some.