CM 40 JHP ammo selection

[Bonhart451]

I am new here, and I appreciate the opportunity to interact with knowledgeable Kahr fans. I recently purchased a CM 40 and it now has roughly 150 rounds through it. I have experienced several failures to feed with Federal HST and Winchester Ranger rounds in various weights. More conventional rounds like the cheaper PPU rounds and FMJ feed well. I certainly understand that I am within the 200 round break-in period, and I am impressed with the overall quality of the pistol. My specific question is this: Do CM 40's that are broken in typically have trouble feeding the more aggressive JHP rounds like HST, Gold Dot, etc.? I know it will vary somewhat from pistol to pistol, but is there any general wisdom in choosing JHP ammo that feeds well in the CM 40? Are any of the premium selections known to feed better, generally speaking?

[Bawanna]

Welcome to the forum Bonhart. That thing should really feed everything you want to feed it.

Your close enough in the recommended but not always necessary break in period.

Give us more details on the misfeeds, where the cartridge ends up. Check the feed ramp of course for any rough spots, the are generally pretty well polished up lately. We'll sort it out.

[Bonhart451]

Bawanna, thank your for the response. I should have taken pictures of the issues, but I didn't think to at the time (and it was cold!). I would classify them as general failure to feed (caught near bottom of feed ramp). I have not owned a CM/PM series in the past, and I have a question regarding the feed ramp. The ramp has been polished to a mirror shine. I assume this was from the factory. I bought the gun used with less than 100 rounds from it, and I know the owner. I don't believe he polished it. My question is this: Is it normal when looking at the feed ramp from the rear (looking down the barrel) for the left side of the feed ramp to be slightly elevated/thicker? When you look at the feed ramp from underneath (looking upward toward the feed ramp bottom), the left side juts out slightly more. I thought this looked odd, but perhaps that's part of the design. I will also explore deburring. I especially welcome any comments on the asymmetric nature of the feed ramp. Thanks again.

[Bawanna]

I think what your describing is normal due to the design offset.

You might pull your mags apart and make sure the springs are installed correctly, that's an easy first thing to try.

So the round isn't even getting up the feed ramp before it's stuck?

[gb6491]

Bawanna, thank your for the response. I should have taken pictures of the issues, but I didn't think to at the time (and it was cold!). I would classify them as general failure to feed (caught near bottom of feed ramp). I have not owned a CM/PM series in the past, and I have a question regarding the feed ramp. The ramp has been polished to a mirror shine. I assume this was from the factory. I bought the gun used with less than 100 rounds from it, and I know the owner. I don't believe he polished it. My question is this: Is it normal when looking at the feed ramp from the rear (looking down the barrel) for the left side of the feed ramp to be slightly elevated/thicker? When you look at the feed ramp from underneath (looking upward toward the feed ramp bottom), the left side juts out slightly more. I thought this looked odd, but perhaps that's part of the design. I will also explore deburring. I especially welcome any comments on the asymmetric nature of the feed ramp. Thanks again.
Yes, this is "normal". Here's a photo of the ramp on my CW9:
http://i68.tinypic.com/20l02dh.jpg
I'd suggest, if hasn't already been done, breaking any sharp edges at the bottom of the ramp.
The green arrow in the photo points to a spot on the ramp where I removed some material to prevent the ramp from hitting the follower: http://www.kahrtalk.com/showthread.php?29039-How-does-this-work

Based on my experience detailed in the linked thread, I'm also going to suggest picking up LakelineLLC's excellent metal follower for your CM40:
https://lakelinellc.com/shop/metal-magazine-follower-for-40-sw-kahr-available-late-september-or-early-october/
To my mind, that's money well spent.

BTW, that's good advice Bawanna has given you.:cool:

Welcome to the forums! :)

Regards,
Greg

[Bonhart451]

Gentlemen, I appreciate the input. This has been very helpful already. Bawanna, I think the HST/Ranger rounds are hitting the very bottom of the feed ramp and sticking for some reason. I think I'm going to clean it, shoot it some more, and if it doesn't clear up, I am going to look at additional feed ramp polishing and perhaps acquiring the metal followers that Greg suggested.

[berettabone]

I realize that I'm talking about different firearms here, but same issue...........................during my break in period with my MK, I had the same thing happening on occasion. I had good springs, I polished my feed ramp to glass. The round tip was catching on the feed ramp, or below on a few occasions. When it did happen, I was shooting Fiocchi range ammo and HST's. I then decided to compare the lengths, just a side by side, with some of the other different ammunition that I had. Fed Hst's, and Fiocchi are longer than most practice ammunition, and are longer than one of my carry loads, Critical Defense. These were the only 2 ammos that I had issues with, and I think that the length may play a part. Also, some of these could have been limp wristing(I ain't gonna lie) but still, only with those 2 ammunitions. What did I do? Nothing.........I knew I had good springs, I knew my ramp was polished, I just kept shooting. Used some different manufacturers ammunitions, and kind of shot through it. I usually like to carry HST's, but I'm still a bit sketchy using them in my Kahr. The Critical Defense has what I feel is a better bullet shape for these small firearms. Never had an issue with those. I could have gone ahead and taken some metal off of the feed ramp, or gotten different springs, but I knew that they were good, so sometimes just shooting through it takes care of it. Nothing wrong with trying some different ammo. Certain guns get finicky with certain ammo. Really for no reason, just happens. Firearms should eat everything they are fed, in theory. Sometimes theory goes out the window.......by the way, welcome.