My K40 - Loose Slide

[Flieger]

K40 - Front to back play in my slide

I took my K40 out today and shot through about 150 rounds. Besides a sore wrist, my K40 developed a looseness where the slide moves front to back just a bit. If I rack the slide, the looseness tightens up or when I put in a loaded magazine. But without the magazine inserted and the firing pin locked back, the slide wiggles front to back.

What did I do, why the play in the slide or what needs attention?

[kerby9mm]

Just guessing from what you described have you checked the recoil spring assembly. When a mag is inserted the follower makes contact with the round stripper bar which would tighten the gun up a little. Disassemble the gun & examine it & post more of a description. Mine go forward & back without the slide stop in but I can't see how that is the problem.

[FLBri]

I would have to agree. A compressed or weakened recoil spring would be the prime suspect.

[Flieger]

This may be the problem, or at least part of it. I compared the K40 with my MK40. The stricker block doesn't fit as tight with the stricker on the K40.

The MK40 is much tighter. There is a wabble between the two parts that mimics the movement in the slide.

Could this be the problem?

I'm still going to replace the recoil and striker springs, but if you think I'm on to something, I'll call Kahr on Monday.
Let me know what you think.

Thanks for you help.

[jocko]

install a new recoil spring. thats ur issue. nuttin wrong with ahything u hve done or the gun either.

You can go to wolffs gun springs and order the k40 reciil srping under the same order as the K9, as they use the same spring. Just ourder the outter spring, They even list a heavier poundage and if it was my K40 I would defnintely order the heavier poundage recoil outter spring. Just sayin

wolffs order #

20# factort springs # 50520
22# heavier spring #50522
23# heavier spring #23

Kahrs recoil springs are made by Wolffs,s o ur getting the best springs on the market, IMO>
Ucan whileur ordering order the 5# striker spring which will really make a nice drop in mod to, u will notice a difference in the trigger pull buyt the lengt of pull will still be the same

[Flieger]

install a new recoil spring. thats ur issue. nuttin wrong with ahything u hve done or the gun either.

You can go to wolffs gun springs and order the k40 reciil srping under the same order as the K9, as they use the same spring. Just ourder the outter spring, They even list a heavier poundage and if it was my K40 I would defnintely order the heavier poundage recoil outter spring. Just sayin

wolffs order #

20# factort springs # 50520
22# heavier spring #50522
23# heavier spring #23

Kahrs recoil springs are made by Wolffs,s o ur getting the best springs on the market, IMO>
Ucan whileur ordering order the 5# striker spring which will really make a nice drop in mod to, u will notice a difference in the trigger pull buyt the lengt of pull will still be the same

Thank you Jocko!

[jocko]

Thank you Jocko!

........................................ customerservice@gunsprings.com

[AFCop]

K40 - Front to back play in my slide

I took my K40 out today and shot through about 150 rounds. Besides a sore wrist, my K40 developed a looseness where the slide moves front to back just a bit. If I rack the slide, the looseness tightens up or when I put in a loaded magazine. But without the magazine inserted and the firing pin locked back, the slide wiggles front to back.

What did I do, why the play in the slide or what needs attention?


Have you been able to resolve the front to back slide play?

I had a similar concern, with my K40 fully assembled you could push on the rear of the slide and it would move forward about 1/8th of an inch so that the rear of the slide was no longer flush with the rear of the frame. I disassembled and reassembled it and cant get it to repeat the problem. I am just wondering what would cause the slide to move forward.

Did new springs fix your issue?

[b4uqzme]

Did new springs fix your issue?

and which pound spring did you use? I'm still running factory but have been thinking about going to 22# for the next change-over. It makes great sense on paper but I haven't had the opportunity to try it out yet. If you went with a stronger spring, can you tell any difference?

thanks

[FLBri]

Have you been able to resolve the front to back slide play?

I had a similar concern, with my K40 fully assembled you could push on the rear of the slide and it would move forward about 1/8th of an inch so that the rear of the slide was no longer flush with the rear of the frame. I disassembled and reassembled it and cant get it to repeat the problem. I am just wondering what would cause the slide to move forward.

Did new springs fix your issue?

I'm glad the issue hasn't repeated itself. No, springs would not be the reason the slide would move an 1/8" forward of the frame. That could only be something out of place in the re-assembly. Apparently when you took it down and put it back together everything seated as it should. Congrats!

[AFCop]

I'm glad the issue hasn't repeated itself. No, springs would not be the reason the slide would move an 1/8" forward of the frame. That could only be something out of place in the re-assembly. Apparently when you took it down and put it back together everything seated as it should. Congrats!

Im glad it hasnt repeated also. Just cant figure out why it would happen. It manually cycled fine, slide stop pin was snapped into place.

Am I correct, that the slide stop pin and barrel lug should preclude forward travel of the slide?

Thanks.

[FLBri]

Im glad it hasnt repeated also. Just cant figure out why it would happen. It manually cycled fine, slide stop pin was snapped into place.

Am I correct, that the slide stop pin and barrel lug should preclude forward travel of the slide?

Thanks.

Yes, That's exactly what I'm saying. Is it possible that the barrel, or recall set up, or something! wasn't seated right and the slide stop was not in the right position?

I just took out my T40 from my office desk. I can't duplicate the condition completely. But, if I PARTIALLY insert the slide stop with the slide pulled back, so that the SS is in front of the lug (rather than through it) I can duplicate the push 1/8" forward condition. But there is no way to fully insert it like this and cycle the slide.

Maybe something foreign was down in the lug/recoil area. When you took it down again it may have fallen out. That's the simplest answer.

[Flieger]

I still haven't heard anything from Kahr yet, but after discussing the problem with several people that know their stuff, it is without any doubt the way the slide stop pin rests in the barrel lug.

Since at this point by looking at both parts, there is wear on the slide stop, but I can't see any appreciable wear to the lug, I will try to replace the slide stop first. If that doesn't work, the barrel is next.

Last week I was talking with John at Magnum Research, had a few questions about the New Baby Eagle 45 I ordered. After telling him the story about how I was dismissed by Kahr concerning my problem, I asked him if now since MR is owned by Kahr, would their service suffer?

Off the subject for a second. Baby Eagles are fantastic guns and they have great service.

Back to the Kahr, I ordered both a 20 & 22lbs recoil spring. I intend to use the 22, but bought the 20 just in case. But the way I looked at it, if the 22 works, that will lessen the shock to the slide stop/barrel lug.

[Flieger]

Imagine when I first called Kahr for help with this problem, the rep told me it was normal. I told him that last weekend I had a chance to visit one of the largest gun stores in my area and they had 4 K40's ranging in age and condition and none of them had my problem.

He said that he would be concerned if there wasn't forward/aft movement. Please Kahr, insult my intelligence. After about 10 minutes of trying to explain how utterly illogical his premise was, it's time to call it a day.

Conversely, when I bought my first Baby Eagle in 9mm, I noticed some pretty ugly mill marks on the slide stop. I called Magnum Research and their response was "I'll ship out a replacement to you immediately".

So my response to that was to buy another BE.