Ammo Chambering Problem

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Went to the range today with my Kahr CM 40 S&W with some new ammo and right off the bat I could not chamber even the first round. I figured oh no, just like the PMC ammo that wouldn't chamber. So I reloaded one of the 6 round mags with Winchester ammo that has always worked and they would not chamber either. I'm thinking what the heck is going on. Maybe the mag went bad so I tried another 6 round mag and got the same results. I then put my 5 round mag in and had no problems at all. Now I'm thinking, both my 6 round mags went bad at the same time?

Anyway, when I got home and started looking at the rounds that would not chamber(about 10 in all), I noticed each one had a deep scratch on the casing. So now I'm wondering, is there something wrong with the gun? I have put almost 200 rounds through it so far so it's still pretty new and just starting to break in.

Any thoughts or suggestions? Can we post pics here? I have a pic of the scratch on the casing.

[DeaconKC]

Without being there, it sounds like you have some grit in the chamber. When you cleaned and lubed it last, if you had a little extra oil in the chamber it can act as a magnet to grit. Since firearms are built with tolerances in the thousandths of an inch, a tiny piece of something will cause the jam you are describing. Really scrub the chamber and barrel with a good spray cleaner and make sure it is spotless. Then try to chamber a round.

[b4uqzme]

here's a recent thread with a similar problem? you might find something helpful in there --- at least about the scratch... good luck wish I could be of more help.

http://www.kahrtalk.com/showthread.php?t=19589

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Thanks for that recent thread, the scratch is almost identical. I'll take down the Kahr tonight and check everything and also check the mags in question. Here's a pic of my scratch.

[Ikeo74]

Why does the picture look like the case is crimped at the top? It that just the lighting or is the case bent? Can you post a picture of the complete case from top to bottom?

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It's just the lighting but I double checked just too make sure. Here's another pic of the same round.

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OK, I found out what is making the scratches, it's the magazine itself when loading it, it rubs up against the metal flange on the right side, the side that the flange is sort of angled down . All of my mags are like that so I guess that's the way they were made.
Maybe I can file down the sharp edge a bit on that side. Another thing I just found out is if I download the mags with 5 instead of 6 rounds, then they will chamber. Could it be that the springs are already starting to wear out after about 80 rounds through each of them?

[Ikeo74]

New springs are extra tight until they get limbered up. They do not wear out that quick. When you load them to max capacity it puts extra upward pressure on the slide and that drag will cause miss feeds. After several hundred rounds the springs will wear in and be more limber. That will let you to load back to max capacity. Until then load all mags 1 short and the problem will go away.

[Tilos]

Removing the sharp edge(s) from the mag lips and polish them with a dremel felt bob with some car polish has worked for me.
Wait that sound funny

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I just happen to have those tools so I'll see what I can do but unlike you, I will not tell anyone Tilos

Ikeo74, I understand what you are saying about new mags and I agree but why would they have worked when fully loaded for the first month and start doing this now? Doesn't make sense.

[hardluk1]

Dirty gritty mag internals from shooting them. break the mags down and detail them just like the handgun. Radius the followers edges and lube and wipe dry.

[CharlieW]

Also CM40's are notorious for broken magazine followers -- you will want to check them when you are detailing the mags. Good Luck!

[Tilos]

If the stamping die was dull those feeding lip surfaces can/could be very rough.

Mass produced items can usually benefit from some "detailing/hand work".
With metal magazines, the inner corner of the lips is a critical surface for functionality, but gets the least amount of exposure in the batch tumbling method used for dedurring/polishing.

Besides polishing is a good way to show love for your stuff, just don't over do it.
It's embarrassing for me to admit, I'm taking a risk here, but I think it's a man thing...can I say that

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I'll detail the mags and check for any problems.

Thanks for the help guys, it's much appreciated.

[jocko]

polish under the feed lips, I wouldbe hesitant to tell u to bend the lips. they are desiged the way they are, but polish the hell out of the bottom of the feedlips and u will be very surprised. Listen tot he comments form these guys,They IMO are right on the money. New springs take alittle while to take their designed set, Check ur followers to see that none are busted. Use the slide lock lever to load that first round. IMO do not try to anual hand rack that first round until u and te gun get well aqcquainted. Kahrs are tight and hand racking can be an issue for some but after a few hundred rounds the guns loosesn up gets very smooth andu get more accustomed to the gun to and then u willbe able to hand rack with ease.....

U did not state when u had these issues if u were hand racking or using the slide lock lever to load that first round. there is a difference..