Slide locks open while firing midway through magazine. Please help.

[RogerP9fan]

When I took my new CM9 to the range for it's first 100 WWB break-in rounds, the slide locked opened halfway through firing a full magazine. Seems like it was the third round that locked the slide back and I just hit the slide stop lever and resumed firing. This happened during the first three magazines and thereafter ran flawlessly.

A member here told me about the test to run. Break down the gun and put the slide stop in the frame. Then slowly insert a magazine loaded with your carry ammo and see if the nose of the first rounds touches or pushes up the slide stop lever. Initially, it did not but I just ran this test again and it is making contact and pushing up the slide stop a little.

What is the solution? Is it OK to file/sand the very edge of the slide stop that makes contact with the rounds?

Should I send it in to Kahr?

Please help.
Thanks,
Roger

[TucsonMTB]

Polishing off some material where you can see that contact is being made is the accepted solution. If the resulting surface is very smooth any contact with the bullet is less likely to move the lever.

However, you should feel free to contact Kahr customer service, just in case they want to send you a replacement slide release lever. If they do, you can proceed with less concern about removing too much material. ;)

[deadhead1971]

I am having the same problem with a Kimber. Kimber's fix is a modified slide stop that is shaved and rounded off.

I have over 3,000 rds through my PM9, and I have had an early slide lock back maybe 2-3 times...no more than that.

[RogerP9fan]

Polishing off some material where you can see that contact is being made is the accepted solution. If the resulting surface is very smooth any contact with the bullet is less likely to move the lever.

However, you should feel free to contact Kahr customer service, just in case they want to send you a replacement slide release lever. If they do, you can proceed with less concern about removing too much material. ;)If I were to remove some metal and polish myself....would buying a Dremel be necessary or could I file, sand and hand polish with some Flitz?
I imagine if I accidently remove too much metal then I'll have the opposite problem - the slide will not lock open upon finishing shooting a magazine. :confused:

[RogerP9fan]

I am having the same problem with a Kimber. Kimber's fix is a modified slide stop that is shaved and rounded off.

I have over 3,000 rds through my PM9, and I have had an early slide lock back maybe 2-3 times...no more than that.Yeah, my CM9 only had the early slide lock back issue with the first three magazine loads and then everything went fine. So, hopefully this will turn out to be a non-issue and I will finally reach that goal I've been striving for - - - >> To be a happy Kahr owner that can trust my gun 100%. Thanks for your input.

[BEARDOG]

If I were to remove some metal and polish myself....would buying a Dremel be necessary or could I file, sand and hand polish with some Flitz?
I imagine if I accidently remove too much metal then I'll have the opposite problem - the slide will not lock open upon finishing shooting a magazine. :confused:

Roger, is this now happening with different magazines since we talked last?
I just wondered because I think the mags are part of this problem as well as the slide lock.

Anyhow, yes you can file/sand and polish it by hand. Just use increasingly finer paper up to like 600-800 wet/dry then polish with flitz, keep doing the check as you go and take a little at a time till it clears all your mags. Also check with an empty mags, that you still lock back the slide with all mags and have a good amount of contact with the mag button on the follower that moves the lock up.

You should call and tell Kahr about it. They will send you another polished slide lock to try.
Then just go ahead and work on this one and if you get it working, use the other for a back-up.

Edit;
I also wanted to add...
2. Do another check and tell us what happens, with the slide in its normal closed/firing position push up on the slide lock to the top and release it. Did it come back down the whole way on its own? Try to push ever so lightly on the front of the slide, backwards like in the direction that you rack the slide. and watch the slide lock did it go down farther? If this is happening the spring pressure may also need increased to help hold that lever down better.

[TucsonMTB]

If I were to remove some metal and polish myself....would buying a Dremel be necessary or could I file, sand and hand polish with some Flitz?
I imagine if I accidentally remove too much metal then I'll have the opposite problem - the slide will not lock open upon finishing shooting a magazine. :confused:
600 or finer grit wet-or-dry production paper is works better than a Dremel because it is more easily controlled and can still produce a mirror-like finish.

Yep! You nailed it. Going too far will not leave enough material for the magazine follower to engage, resulting in the opposite problem. ;)

Edited to add: Shucks! BearDog's message crossed mine in the ether and says effectively the same thing. I'm just not quick enough. ;)

[wyntrout]

Email Kahr and explain your problem. Maybe they will send you another slide lock lever. You can try removing a bit of material. There are posts on this site with pictures and explanations about how to do that... not CM's but other pistols.

My P380 did that and I fiddled with it and the magazines for months. I was talking with the head of Kahr Customer Service about my PM45 and mentioned the problem with the P380 locking open before empty. He said send it in with the PM45 that FedEx was going to pick up anyhow.

They replaced the slide lock spring and polished the slide lock. I haven't had a problem since.

Wynn:)

[jocko]

If I were to remove some metal and polish myself....would buying a Dremel be necessary or could I file, sand and hand polish with some Flitz?
I imagine if I accidently remove too much metal then I'll have the opposite problem - the slide will not lock open upon finishing shooting a magazine. :confused:

not go with a dremell thgey tend to take off to much in a hurry. a small fine file at sears will do the trick and then justr resmooth with fine paper and retest again. U don'tneed much clearance, so don't make tha tyour goal if they slide past ok and actually if they slide past and toucht hat slide stop and it doesn't do anything, just stop rigtht5 there and shoot it like u stole it. U know what needs to be done. getting a new slide release lever is not necessary, but I would call kahr and ask for IAN OR JAY and tellthem what you have found, but dn't mention the filing thing, and I am sure they will send u a new slide stop lever to solvew the issue. That way u will have a back up in case u somehow ruin the one now. Justy go slow, it is not rocket science. Have u tested this with defense hp ammo to??? Be very sure ytour thmb is nothitting that lever either and causing it. The lever should not move doinbg the test u did..

for sure don't send it back, u can certainly do a BETTER job yourself, ..

[wyntrout]

It's not the top round properly seated that's causing the problem. It's the top round that's advanced a bit after the initial chambering of a round. The next and subsequent rounds are dragged forward and that's where they can contact the slide lock actuator. Try moving the top round a bit forward to see if it contacts the actuator. You can get an idea by chambering a round from a full mag and then removing the magazine to see where the next round is sitting... and the one after that... etc. The advance varies as the magazine spring pressure is lessened.

You can use a stone, or medium sandpaper, then finer and finer sandpaper or Dremel POLISHING, not grinding.

Wynn:)

[RogerP9fan]

These are some really helpful tips and points. I really appreciate them as I wanna get 'er running right. I'm REALLY digging this little CW9.

[RogerP9fan]

Roger, is this now happening with different magazines since we talked last?
I just wondered because I think the mags are part of this problem as well as the slide lock.

Anyhow, yes you can file/sand and polish it by hand. Just use increasingly finer paper up to like 600-800 wet/dry then polish with flitz, keep doing the check as you go and take a little at a time till it clears all your mags. Also check with an empty mags, that you still lock back the slide with all mags and have a good amount of contact with the mag button on the follower that moves the lock up.

You should call and tell Kahr about it. They will send you another polished slide lock to try.
Then just go ahead and work on this one and if you get it working, use the other for a back-up.

Edit;
I also wanted to add...
2. Do another check and tell us what happens, with the slide in its normal closed/firing position push up on the slide lock to the top and release it. Did it come back down the whole way on its own? Try to push ever so lightly on the front of the slide, backwards like in the direction that you rack the slide. and watch the slide lock did it go down farther? If this is happening the spring pressure may also need increased to help hold that lever down better.Yes, I had two "early slide lock opened" malfunctions today with two new Kahr 6 round magazines. Neither mag was used the first outing in which I had three of these malfunctions. I now have 200 rounds through.
I did your test by pushing up the slide stop lever with the pistol in normal firing mode and it does return to the normal position immediately.
Thanks for you interesting tests and helpful suggestions.