CW380 Slide Stop Modification

[holygeez03]

I have owned a CW9 and CW380 for many years now and I am fairly familiar with both pistols, somewhat thanks to forums like this... I have always been able to find answers to my questions with some internet research.

My CW380 has performed fairly well, but I don't shoot it that often... it has cycled all of the practice and defense ammo that I have put through it, except Geco due to the case rim not fitting under the extractor, but I am not changing or modifying the extractor due to one brand of ammo that I will never buy again. I believe it is the same problem with Fiocchi ammo, but I have never tried that brand.

Eventually the tab that keeps the slide-stop in the gun cracked off and Kahr sent me a new slide-stop. It appeared to me that since the replacement part was undressed, I may have issues with bullets in the magazine interfering with the slide stop. Sure enough, the clearance was too close for comfort with most bullet profiles (I have many for testing) and made a TON of contact with Federal HST bullets.

So I started grinding on the stop in order to improve bullet clearance. Everything should clear now, but I have not been able to confirm with live-fire... except there is still a lot of contact with the Federal HST rounds. I would like my pistol to be compatible with all of the common defensive ammo on the market...

If I continue to remove material from the slide-stop, it is almost guaranteed that an empty magazine will not lock the slide back as intended... but I am not sure if I care? It is probably more important for me that there is plenty of clearance with all bullet types than the slide locking when empty, since I don't ever carry a second magazine anyway. If I feel like I may need more bullets, I will bring a higher capacity firearm.

I do like the Kahr's ability to lock the slide, but I only do this manually for safety reasons or to directly load the chamber (I have a loading method that I am cofortable with, which is in my opinion safe and will not damage the extractor).

Has anyone else out there ever removed so much material (intentionally or otherwise) from the slide-stop that it no longer locked when empty? Is there any reason that this will cause any issues (other than lock-back)?

[Bobshouse]

I think the slide stop pin on a CW model is a mim part, not solid stainless. From what I understand mim parts are only case hardened and once you break that exterior material they will become brittle. Someone with a better answer will be with you shortly, welcome to the board.

[holygeez03]

I don't think you understand what I am modifying... I am not grinding the actual barrel link pin or the portion of the slide-stop that actually locks the slide... only the part that sticks out in order for the magazine follower to actuate the stop.

[Old No7]

Everything should clear now......... except there is still a lot of contact with the Federal HST rounds.
So... Simply choose another good self-defense round that clears and is totally reliable.


I would like my pistol to be compatible with all of the common defensive ammo on the market...
Unless you got a lifetime supply for free -- why???

And would you ever shoot "all of the common..." in one SHTF scenario, or range session anyway?


If I continue to remove material from the slide-stop, it is almost guaranteed that an empty magazine will not lock the slide back as intended...
I'd agree with you, and I personally wouldn't do it or risk it just to shoot "1 type of ammo" when there are so many other good brands/types available.


Has anyone else out there ever removed so much material (intentionally or otherwise) from the slide-stop that it no longer locked when empty?
I think the answer is "very few" otherwise, but "intentionally"??? -- That's probably soon to be "only 1 that we know of..."


Is there any reason that this will cause any issues (other than lock-back)?
How about...

* Resale value

*Or not knowing when you're "out" in a really bad SHTF scenario?

(When I agree, I'd rather have MUCH more than a little 380...)

If it were me, I'd give up on the HST ammo and use what works and is reliable and doesn't impact the designed/safe operation of the gun.

Just my thoughts...

Old No7

[Old No7]

< removed duplicate post >

[SlowBurn]

If it were me, I'd give up on the HST ammo and use what works and is reliable and doesn't impact the designed/safe operation of the gun.


Yep. That would be my approach, but then I wouldn't grind on it in the first place.
But since you're the handy sort, the other way to look at it is the slide stop is not that expensive and if you grind off too much you could just get another one and start over. Also, if you do get another one, consider the P380 slide stop which the same price last I looked. Its interchangeable and is not a mim part.

[gb6491]

I have owned a CW9 and CW380 for many years now and I am fairly familiar with both pistols, somewhat thanks to forums like this... I have always been able to find answers to my questions with some internet research.

My CW380 has performed fairly well, but I don't shoot it that often... it has cycled all of the practice and defense ammo that I have put through it, except Geco due to the case rim not fitting under the extractor, but I am not changing or modifying the extractor due to one brand of ammo that I will never buy again. I believe it is the same problem with Fiocchi ammo, but I have never tried that brand.

Eventually the tab that keeps the slide-stop in the gun cracked off and Kahr sent me a new slide-stop. It appeared to me that since the replacement part was undressed, I may have issues with bullets in the magazine interfering with the slide stop. Sure enough, the clearance was too close for comfort with most bullet profiles (I have many for testing) and made a TON of contact with Federal HST bullets.

So I started grinding on the stop in order to improve bullet clearance. Everything should clear now, but I have not been able to confirm with live-fire... except there is still a lot of contact with the Federal HST rounds. I would like my pistol to be compatible with all of the common defensive ammo on the market...

If I continue to remove material from the slide-stop, it is almost guaranteed that an empty magazine will not lock the slide back as intended... but I am not sure if I care? It is probably more important for me that there is plenty of clearance with all bullet types than the slide locking when empty, since I don't ever carry a second magazine anyway. If I feel like I may need more bullets, I will bring a higher capacity firearm.

I do like the Kahr's ability to lock the slide, but I only do this manually for safety reasons or to directly load the chamber (I have a loading method that I am cofortable with, which is in my opinion safe and will not damage the extractor).

Has anyone else out there ever removed so much material (intentionally or otherwise) from the slide-stop that it no longer locked when empty? Is there any reason that this will cause any issues (other than lock-back)?
holygeez03,
While I don't know if it will be as effective with a 380 slide stop, I did modify a .45 slide stop because some profile rounds would hit it.
I saw that to totally eliminate the contact I would probably have to grind away material on the stop to a point that the stop would no longer lock the slide back.
I also saw that while the rounds would lift the stop, they did not maintain the same contact point and eventually reached a point where the stop would fall away. I decided to reduce the time the rounds would be in contact with stop believing that less time in contact translates to less lift of the stop's lever. I accomplished this by removing material from the top of stop's leg that that contacts the follower:
https://s9.postimg.org/5fjhw9itb/DSC04304_copya.jpg (https://postimages.org/)
After doing this and properly adjusting the slide stop spring screw/spring (adjusting the slide stop spring screw and spring may be the more important of the two), I have not had the slide of my CW45 lock back unintentionally.

As to your question: "Has anyone else out there ever removed so much material (intentionally or otherwise) from the slide-stop that it no longer locked when empty? Is there any reason that this will cause any issues (other than lock-back)?"
Grinding the stop to that point will cause no other issues other than the slide not locking back. I have ground the stop back to that point on a GSG 1911 .22 to prevent damage to the stop notch on that pistol's aluminum slide.

Regards,
Greg

[holygeez03]

I went ahead and ground it down...it really seems like a bad idea to have a part with such small clearance between it and the bullets in the magazine... it's not ONLY with HST rounds, but they are the worst offenders I have seen based on bullet profile.

Now I have much more peace of mind that the slide-stop extension won't interfere and either inadvertently lock the slide mid-magazine or cause a FTF...

Yes, the gun will go "click" after I expend all 7 rounds and pull the trigger again, but this is really not any different from revolvers (except with 5 or 6 shots) that have defended lives for decades. The slide stop still functions perfectly for manual lock-open, which is more useful to me with this particular firearm than lock-open on empty.

As stated, I can easily get another slide-stop if I change my mind. Are the P380 slide-stops really still machined and not MIM? I find it VERY hard to believe that a part like that can be made in a non-MIM fashion for $25... and how/why would it be the same price as the MIM part? I have a feeling they are both MIM now, except maybe the actual barrel pin? And the only real difference is the slightly longer pin on the P380?

[holygeez03]

NIce work Greg... I started by doing something similar on the CW380 stop... instead of grinding "straight back" I made the protrusion angled to complement the bullet profile... it certainly worked better that way, but the clearance in the 380 is so tight that I still didn't like it and I have no way of knowing how the cartridges are going to move around inside the gun during live-fire.

In my opinion, I have reduced a significant point of potential failure, at a tradeoff that makes little difference to me based on my planned usage.

[Ed M]

Are the P380 slide-stops really still machined and not MIM? I find it VERY hard to believe that a part like that can be made in a non-MIM fashion for $25... and how/why would it be the same price as the MIM part? I have a feeling they are both MIM now, except maybe the actual barrel pin?

I'm not diming out my source, but you'd be correct. ALL Kahr slide stops are MIM, but the premium series is 2 piece, with the pin being ground, and not machined. It's then pressed into the MIM outer part.

A fully machined from bar stock slide stop with all that required machine work would cost a fortune, and one can easily see mold marks on the premium series slide stops that wouldn't be there on a 100% CNC machined part.

[holygeez03]

For those wondering... all of my premature lock-back issues went away after grinding the "follower tab" portion of the slide-stop almost all the way down. As stated, this prevents an empty magazine from locking the slide, but I don't care.

Unfortunately, the slide-stop tab that holds the stop in the gun broke off again. Since this now happened to two different slide-stops, I contacted Kahr. To my surprise, they provided a shipping label to return the firearm... it took almost 8 weeks, but the firearm was returned to me with a P380 style "premium" slide-stop... as discussed above, the P380 slide stop is still MIM, so I'm not sure if it will be any stronger/better... but maybe the MIM process and/or quality control is better for the P380 parts.

Kahr service also decided to "polish the slide-stop notch" on my slide... and in doing so, the material between the top of the notch and the slide rail was so thin that is was almost gone and creating a hole in my slide rail with razor sharp edges. So back to Kahr it went... and this time they expedited the service.

My firearm was returned to me again... this time with a replacement slide. My CW380 is an early model and the replacement slide is of MUCH lower quality. Mainly the machined edges and especially the slide serrations. The cuts are just not clean and there is excess material left behind. This gun is definitely "function over form" so I don't need it to be a work of art, but the lower quality is still disappointing and makes me wonder what other corners have been cut.

Anyhow... the gun suffered from significant premature lock-back with several types of target and defensive ammo... almost definitely from the new slide-stop... so the Dremel tool came out again and I ground down the "follower tab" on the slide-stop to a point where it just barely allowed an empty magazine to actuate the slide-stop.

The premature lock-backs were definitely reduced, but still occurred. So I ground the follower-tab all the way down as soon as I got home. I haven't had a chance to live-fire test again. I suspect the premature lock-backs will be gone... and hopefully the new slide/stop combo doesn't break the stop anymore.

In my opinion, the VERY tight clearance between the slide-stop and cartridges (bullets) in the magazine is a major design flaw of the CW380... especially since the magazines allow the cartridges to slide forward, increasing the chance of contact with the stop. Considering this is a 100% self-defense oriented firearm, having a design with such a high likelihood of stopping the gun is unacceptable.

I am going to re-start my search for a different "pocket gun". I wish someone would make a pocket gun with CW380-size, Glock/Ruger reliability, Glock/Kahr trigger... 9mm would be wonderful, but probably not 100% feasible. I have looked at the LCP, G42, Spectrum, RM380...

In the meantime... having the ability to manually lock the slide is still important for loading the chamber directly... and the lack of slide-lock when empty does not bother me with this particular firearm and it is far more important to me that it NEVER locks back before empty. I believe this is how the original LCP operated (manual slide-lock only)?

[yqtszhj]

My cw380 has been good so far. On the other pocket pistols you mentioned, my wife’s RM380 (that she NEVER carries has been flawless. The trigger pull is LOOOOONG.