Premature slide lock

[jdmac44]

I have a Kahr MK9 that has a tendency for the slide to lock back prematurely, before the magazine is empty. It will even do this with my arm and wrist locked out (I'm 6'3", 230 lbs, so I don't have a problem holding it firmly). I realized that the slide retention lever's spring wasn't pressing down as much as I thought it should and so I reasoned that the lever must be flipping up with the recoil. I contacted support and they sent me a new spring (thank you!), but the spring they sent me was the wrong one (oops!). So rather than go through that again, I took the original spring out and gently bent it so that it would press the lever down more firmly. I finally was able to get to the range last week and I had the same problem, it was raining so I didn't put a lot of rounds through, but it locked back on me once in two magazines. Any other ideas? Oh yes, and it will do this with standard pressure el cheapo FMJ rounds as well as high quality high pressure JHP rounds. If all else fails, I'm going to buy an extra slide retention lever and file down the bit that holds the slide back! A few compact guns down even offer slide lock, so why not?

[jocko]

u are probably on the right track. About the only other thing that can cause premature slide lock is one of those rounds is hitting inside the slide lever, and there fore engaging it.

Take ur slide off, insert the slide lock lever and then insert a loaded magazine and see what that top round is doing on the left side. Is it hitting theat slide lock lever??If so you should see very easily that lever going upward when you insert a loaded magazine. If so callkahr and get a new slide lock lever from them. I would doubt if it would be that little spring thing, for its design is to always to be pulling the slide lock lever down ward and never upard. Only the magazine follower moves the slide lock upward.

Be very sure your thumb is possably not engaging that slide lock lever also. A good test is to shoot it left handed to see. Normally the MK9 will shoot anything that goes into the pipe. My bet is a faulty out of spec slide lock lever. Please keep us posted on how you resolved this...

[jdmac44]

Cool thanks, I'll check it out and get back to you! I have been watching my thumb, but I hadn't thought of anything interfering on the inside.

The toughest thing about this is getting to a range around here to test the latest theory. The closest ones are 45 minutes away, I let my membership lapse at mine when I thought I was going to move out of state and so I have to go with a buddy to one of theirs, when they have time to go. Some only allow you to join in the spring, some have closed membership because of the rush of new gun owners due to our new administration, then there's the indoor range that charges $15 an hour.

[jocko]

Cool thanks, I'll check it out and get back to you! I have been watching my thumb, but I hadn't thought of anything interfering on the inside.

The toughest thing about this is getting to a range around here to test the latest theory. The closest ones are 45 minutes away, I let my membership lapse at mine when I thought I was going to move out of state and so I have to go with a buddy to one of theirs, when they have time to go. Some only allow you to join in the spring, some have closed membership because of the rush of new gun owners due to our new administration, then there's the indoor range that charges $15 an hour.

thing indeed requires you to do some shooting witht he left hand to check that part out but the rounds hitting the slide stop on the inside you can check right in home to see if it is happening.

to my knowledge that is the only two things that can cause the slide stop to engage without permission, your thumb hitting it and u not knowing it or the slide stop is being hit by the bullet on the inside as it comes up in the magazine.

[jdmac44]

Okay, I just checked and the rounds do not interfere with the lever at all. I looked at my grip and I naturally do not keep my thumb anywhere near the lever. I looked a little more closely at the spring with the slide off and the slide stop lever in and noticed that the spring wasn't even making contact with the lever for a couple of millimeters, which as I had already noticed before gave enough play for the lever to go up and catch the slide. I've bent the spring down to the point where it actually contacts the lever and now there is very little play, it is controlled by the spring. I almost made a YouTube video to demonstrate but I already bent the spring, so I think it's best to leave it. I think you know what I mean. :) I won't be able to test it immediately, but I hope to soon, maybe once it finally stops raining and soaking the local ranges for awhile. :mad:

Thanks for your help! I'll report back once I'm able to shoot again.

[jocko]

I bet u fixed the issue. that little springhy thing has to make contact as u noticed. Nice job jdmac...

[jdmac44]

I think so! Thanks for your help, I don't know why I didn't think to remove the slide and put the slide stop lever back in. That helped immensely to see what what going on in there. Sometimes I get tunnel vision on these things. Thanks for your help.

I need to go to the range and rebuild my confidence in my weapon! lol

[Speedy]

Im having the same problems with my MK9.
Its about a 8 months old. I put maybe 400 rounds thru it and it still locks the slide with ammo still in the magazines! :O
Shot with my left hand, still does it,
checked the mag to see if the ammo was touching. NOPE (it comes very close but does not touch).
I've even tried different ammo and still nothing helps.
Any Advice?

[jocko]

DO WHAT JDM44 DID TO HIS SLIDE STOP SPRING.

Only 3 things can cause a paremaute slide stop engagement.

#1, thumbs hitting it
#2 bullets hitting on the insde of the slide stop lever causing it
#3 weak or bent slide stop lever spring, causing to much freeplay

nothing else can cause that. eliminate the possables

Also go to the kahr tech section and hit on the propper prepping of your new kahr, it addresses this little spring thing to and how to adjust. also go to gb6491 sticky on the kahr tech section of cw45 issues. he has some excellent photos of what this little springhy should look like if all is right. My thoughts are tha tyour slide stop lever has to much free play and needs that little springhy tweeked..

[Speedy]

oh, sorry, forgot to mention that. spring is nice and firm.
i'll check the prepping of the kahr ( i remember reading something about 10 steps to prepping or something like that a while back. i remember watching tv and racking the slide 500x's lmao)
cool, thanks man, i will check out those pics of gb9491

[Speedy]

hmmmm, looks like the pm45 and mk9 have different set ups when it comes to the slide stop spring......

[jocko]

I don't think so, both use that little sprinly on the left side of the frame by the slide stop lever.

[Speedy]

Here's the MK9

[Speedy]

Here's the PM45. They are different.

[jocko]

well in a sense ur right but my point was that little springy might need some tweeking. They both work the same way.

sorry about that..

[Bawanna]

Slightly difference configuration, same concept. The K's have the spring on the right side, totally different and stronger in my estimation.

[Bawanna]

Jocko beat me again, he wins, I lose. And history repeats itself.

[Speedy]

I called Kahr and they said its not the problem
hmmm
*scratches head*
i mean it IS tight but not as tight as my K9 slide stop. I told the tech that and he said its not the problem. He indirectly blames the shooter. I shoot lots of other guns with no problems. Friends and LEO friends of mine have had the same problem.
*scratches head again*

[Speedy]

Right, the K9 is VERY TIGHT. I have to tap the slide stop to dissassemble.
With the MK, i can push it out with my finger. Its not loose, just snug.

[jocko]

I called Kahr and they said its not the problem
hmmm
*scratches head*
i mean it IS tight but not as tight as my K9 slide stop. I told the tech that and he said its not the problem. He indirectly blames the shooter. I shoot lots of other guns with no problems. Friends and LEO friends of mine have had the same problem.
*scratches head again*

this. put a dab of great on the springhy. On the tip and also on the back side. That is what snaps into the slide stolp lever.If you look at that lever u will see a groove right by the flat peace of the slide stop. that back part of that little psringhy snaps into that groove. That is what keeps the slide stop from coming out accidently. Some are tighter than others, but nothing like the K9 slide stop spring. Mine is very tight and Ihave to give it a tap with something hard, which is OK, as it is designed to work that way. Forget how other guns work .I have never seen a slide stop set up like the polymer kahrs or the MK kahrs. If u look closedly at it that little springhy thing does two distinct functions.#1 It brings the slide stop downward and #2 It locks the slide stop in the frame also. really kindof ingenious, although I wish the polymer kahrs springhy screw went into a metal insert, like the MK series threads into. But again, they really don't give any issues unless you fokk with them..:86:

[Bawanna]

With the slide off is there pretty good spring pressure keeping the lever down. Not slop or take up then.

Wonder why they would say that isn't the problem. It's very easy to hit the lever with the thumb but with multiple shooters having the same issue thats not likely the culprit.

You've done the slide off, install slide stop, insert full magazine inspection to make sure the bullets are hitting the lever?

[Speedy]

You've done the slide off, install slide stop, insert full magazine inspection to make sure the bullets are hitting the lever?

yea, actually that was the 2nd thing i did after making sure my thumb wasnt grazing the slide stop.
The bullets come VERY CLOSE but do NOT touch the slide stop. it looks like very tight tolerances and the gun is made right. so i dont know what to think:confused:

[jocko]

u might see if kahr would send u a new slide stop to try to trouble shoot this. a call to kahr and talking to Jay or eion and explaining exactlyh what you have done and what you have checked over to. they might send you a new slide stop in hopes thissolves the issues. after that the gun is gonna have to go back. I would also ask kahr tosend you a new slide stop spring. Yourws might look good but it could not be doing what it is designed to do. It is ano brainer i the MK's to replace. Not sure but I think that little torx screw is a #6 torx too. U can buy it at sears for about $5.

[Speedy]

Cool, will do 1st thing tomorrow! Thanks Jocko!
Be sure and check out thase grip pics from the other thread...
http://kahrtalk.com/showthread.php?p=59984&posted=1#post59984
i'll try and post the final pics tomorrow morning

[Speedy]

they want me to send it back *rolls eyes*

[CarlCyrus]

Had a perfect run of 300 rounds with 115gr ball ammo, then occassaional slide lock with PD rounds. See my thread with pics as to why this might be happening:
http://kahrtalk.com/showthread.php?t=6066

BTW, the pic in that link was with my new PM9. Will check the same thing with my older MK9 and post similar pics.

Carl

[CarlCyrus]

SOLVED slide-lock problem. See the conclusion of my other thread on this.

http://kahrtalk.com/showthread.php?t=6066&page=2

Carl