[HighValleyRanch]

I have a Kahr P45 which works flawlessly. It had the stainless slide, so I thought I would like the Black Diamond slide better. So I ordered a new p45D slide from Kahr and recieved it today. I proceeded to swap out all the existing parts from my old slide over to the new Black Diamond slide, and it didn't work. It would not release the striker. The slide gets stuck and since you can't release the trigger, in order to remove the slide, you have to disassemble the slide with the slide locked back. So after I did that three times, making sure ll the parts were in correctly, I put the old parts back into the original slide and it worked perfectly.

So I inspected the new slide against the old slide, and it seems that tolerances on these parts are not very exact. I can see that the striker channel is not the same place. If if place the old striker in the old slide channel, it measures 1/16 inch from a straight edge across the bottom of the slide. If I measure the striker arm on the new slide, it measures 1/32 inch from the straight edge held across the slide bottom. This is indicating that the striker arm is now sitting too low for the tirgger cam to release.

So I mounted the stripped slides on the frame with the backplate rmoved, and only the striker block and the striker to watch the release of the trigger cam on each slide. On the old slide, there is a definitel release point as the trigger cam reaches it's apex and then releases the striker arm. But on the new slide the trigger cam does not release the striker arm because it is too long because of the difference in the height of the striker channel.

You would think that with CNC all parts would be indentical. So my question is, Do all parts on the Kahr have to be hand fitted like on a 1911. I imagine that if I took a little off the striker arm, then maybe it would release. But then this means that it would be too short for the old slide configuration. My only hope would be to order a new striker from Kahr so I would not have to alter the old one. That way I could always change slides. I'm thinking about having the old stainless slide milled for an optic mount, so I want the option.

So is fitting the striker arm to the trigger cam akin to fitting a 1911 sear to the hammer? Does it change the point of release as far as the trigger pull length?
The old slide, look at the clearance to the straight edge, about 1/16 inch

And this is the clearance to the new slide:

 

[HighValleyRanch]

When I have the slide mounted on the frame with the backplate off, you can see exactly what is happening. Because the striker chamber is lower on the new black slide, the old striker arm or tab sits 1/16" lower, so the trigger cam cannot get past the tab to release the striker. I would have to take off 1/16" or maybe a little less for the striker to be released by the cam. But it feels like the striker tab is hardened steel, so it would be a job taking it down?

 

[HighValleyRanch]

UPDATE: I call Kahr customer service this morning to talk over the situation with the new slide I received. They could not have been more friendly or helpful to try and work with me on the problmes. Sales transferred me to a gunsmith who understood what I was describing, and they told me to ship back the slide so they could check out the tolerances. Will update when I find out more.

 

[BillACP]

Good to hear...Kahr Tech will get you taken care of...

 

[HighValleyRanch]

UPDATE: April 13, 2021
I got a response email from Kahr saying that the new Black Diamond slide that they sent me and I returned was indeed out of spec, and they are in the process of sending me a new on in spec.
The CS has been very repsonsive and helpful! Will repost when I recieve and get it working!
Received the slide yesterday, switched over all the innards and sights and the Kahr P45 is now working perfect with the new black diamond slide.