New CM45 issues

[Zephhyr]

Primary issue:
My new CM45 has a very consistent (75-80%) failure to fully chamber a round.

The best I can describe the issue is, when a round is stripped from the mag it begins to enter the chamber normally, once the round moves forward enough to clear the mag lips the next round pushes the rear of the first round far enough up the breach face causing the round to bind about half way into the chamber.

A sharp smack to the slide usually if enough to fully chamber the round. If I drop the mag, quite often the round will finish chambering.

It happens loading the first round and during shooting.

I put 250 rounds of various types though her and they all act about the same.

I polished all the internals the best I could, tried one of my 1911 mags all to no avail.

[CJB]

Disassemble the slide. Make sure the extractor is assembled right and not binding

[BEARDOG]

My CM45 has a constant success rate of running 100% ;)... But if it was doing what yours is this is what I would try looking at first.

Lube it well (I use grease)
Polish feed ramp and chamber
Polish extractor and breech face
Check tension on extractor (a shorter extractor pin can be made out of a 1/8" drill bit shank to do some testing)
Polish mag feed lips
Make sure ammo passes the "plunk" test
Request a new RSA from Kahr

That's all I got this early in the AM, Good luck!

[yqtszhj]

Yep, everything CJB and beardog said. I'll add 2 things.

1. Make sure the chamber is really clean. In particular the upper part of the chamber. That is where carbon will build up on mine.
2. Make sure you have a good grip. I duplicated that exact problem with mine by shooting with a not tight enough grip.

Keep it lubed good the first 300 rounds. Mine is 100% now so hang in there.

[CJB]

Disassemble magazine, make sure spring is oriented correctly.

[smokersteve]

Send it back to Kahr on their dime so they can fix it.

[TheTman]

I'm finding the slide on my unfired CM45 to be VERY stiff, and very difficult to chamber a round, I did most of the new Kahr prep, except for racking the slide 200 times, it's so stiff that it requires too much effort. I figured I'd just take it and shoot it a bit and see if that loosened it up some, there is nothing binding or anything, the spring is just so damn strong, that it is a bear to rack the slide? is this normal? lubed the hell out of the inner guide rod, but that didn't seem to help. I can't see it, but I wonder if perhaps it is bent just a hair or something to keep it from sliding into the outer guide rod smoothly. I'm off to the range in a bit, so I'll see how things are if it makes it through the break in.

[CJB]

Yes, expect the CM series in 9mm, 40 S&W or 45 ACP to be tight - very tight. The springs are quite stiff.

Racking the slide by hand does diddly squat to the recoil spring, but may improve hand and arm strength.

The spring is made "to become the spring it ought to be". Rapid, forceful cycling, much more rapid and forceful than hand cycling, must be applied to get the spring to be ideal.

Why is this so? Because when you're dealing with short slide travel, almost zero overtravel to pick up a fresh round in the magazine, and lightweight parts, recoiling parts must be very carefully controlled. The smaller, lighter, the pistol is, the more critical this becomes. Springs, by their nature, take a "set" with intital use. Kahr, or any manufacturer, has two choices. Those are, put in a spring that is light, but have you change it every 200-300 rounds for another - because it takes its "set", or, give you a spring that is stiff as hell, and will soon become an optimal spring that is a lot easier to work with. Rightly so, they chose the latter.

At one time, I used to think "just shoot whatever" and get it broken in. My thoughts have refined to the point that I now suggest firing the strongest, hottest, most powerful ammo you can get your hands on for break in. The break in will go better - you might save money by shooting less rounds! And it will go more quickly. The harder you cycle the action while shooting the better off you're going to be. Fewer intial problems during breakin, and a nice limbered up recoil system to show for it when you're through.

Just my 2c worth

"And shoot the fokker like you stole it!"

[jocko]

Yes, expect the CM series in 9mm, 40 S&W or 45 ACP to be tight - very tight. The springs are quite stiff.

Racking the slide by hand does diddly squat to the recoil spring, but may improve hand and arm strength.

The spring is made "to become the spring it ought to be". Rapid, forceful cycling, much more rapid and forceful than hand cycling, must be applied to get the spring to be idea.

Why is this so? Because when you're dealing with short slide travel, almost zero overtravel to pick up a fresh round in the magazine, and lightweight parts, recoiling parts must be very carefully controlled. The smaller, lighter, the pistol is, the more critical this becomes. Springs, by their nature, take a "set" with intital use. Kahr, or any manufacturer, has two choices. Those are, put in a spring that is light, but have you change it every 200-300 rounds for another - because it takes its "set", or, give you a spring that is stiff as hell, and will soon become an optimal spring that is a lot easier to work with. Rightly so, they chose the latter.

At one time, I used to think "just shoot whatever" and get it broken in. My thoughts have refined to the point that I now suggest firing the strongest, hottest, most powerful ammo you can get your hands on for break in. The break in will go better - you might save money by shooting less rounds! And it will go more quickly. The harder you cycle the action while shooting the better off you're going to be. Fewer intial problems during breakin, and a nice limbered up recoil system to show for it when you're through.

Just my 2c worth


I could not have said it better, well actually I would have spiced it up a tad. Just sayin

[CJB]

I fixed it Jocko....

[TheTman]

I went down and put a hundred some rounds through it, and it has loosened up to the point it's not such a struggle to rack the slide. Had a few failures to chamber, a couple of rounds that stuck in the magazine, and that sort of thing. I experimented with it some, and found it very sensitive to limp wristing. I stayed and shot until the range filled up, and not liking crowds, I ended my shooting day.
The little guy is plenty accurate. I kept my target distance around 5-10 yards. And most of the holes were close or in to the x ring on the B-27, most of them just outside of it. With quite a few flyers. I did well with 5 and 6 round mags, but didn't like the 7 round ones much. I think it was starting to break in, the last 22 shots, 2 5-round mags, and 2-6 rounds went off without a hitch. But the place was filling up, and I don't like to be around that many people shooting unsupervised. At one point one of the range officers stopped by when he saw me racking the slide after some malfunction and I told him it was new and I was breaking it in, and asked to see the pistol, so I gave it to him, and he racked the slide and damn that's stiff, and I was like yep, then he proceeded to tell me all kind of crap about Kahrs, and I told him this was my 4th one, I know a little bit about them. Then he said that he'd put about 500 rounds through it before he carried it, and walked off. I heard him talking up Glocks earlier to someone else, so I imagine since it wasn't a Glock it probably wasn't worth owning to him. I think it's going to be a good pistol, once it's broken in. There were no real surprises, just the normal break in failures. I attribute many of them to getting distracted and limp wristing a few. All of the ammo I used was WWB 230 GR FMJ. I didn't think recoil and muzzle flip was any worse than the CW. I was getting tired by the time the crowd arrived, so that was a good stopping point anyway. My groups were getting larger and larger and the laser dot was moving around quite a bit. So the CW40 will continue to be my CC weapon for now. I can slip out back and fire a couple mags here and there to finish breaking it in. We are only supposed to shoot shotguns now that I've been annexed, but I just go in my mini-barn and open the back door and shoot from inside it, I think that baffles the noise well enough that you can't really hear much of anything very far away, or tell where it's coming from. That puts my berm farther away, than I want it, so I suppose I will take the front loader and make a new berm closer to the back door of the barn. For now I just shoot at a target I put at the bottom of large old cottonwood tree.

[muggsy]

I broke in my Kahr pistols using PMC Bronze ammo. I cleaned and lubed both guns every 100 rounds. I didn't start carrying my CM9 until I had about 500 rounds through it and was totally confident in it's performance. Since the initial 200 rounds I haven't experienced a single failure of any kind. That's a pretty decent track record.

[TheTman]

My carry pistol has to have at least 200 trouble free rounds before I carry it. That really sucks when you get to around 190 and you get a stovepipe. But that's a failure so the count starts over.

[jocko]

My carry pistol has to have at least 200 trouble free rounds before I carry it. That really sucks when you get to around 190 and you get a stovepipe. But that's a failure so the count starts over.


unless one does not know what caused th4e swtovepipe, I would say he would not have to do the recount. Hell it could hgave been a bad casing,OAL bullit, Possable improper grip, could be tired shooter if he wqas at round 190 even. thats alot of rounds. The 200 round thing by kahr is a number they pulled out of the hat, IMO it is not gospel. Just sayin. course each ot his own way of breakingin his weapon and calling it good to go.

[Bawanna]

Back when ammo was plentiful (as it should be) and affordable (as it should be) I had my own criteria which usually entailed 750 rounds with zero failures to make it to the belt.

That meant if at round 736 something didn't work, back to zero.

Nothing to do with manufacture recommendation or anything just a preset comfort level for myself.
I don't recall any of my guns of that period not making it the first time around.

Now days with the current state of affairs 50 good to goes and we're good to go. Course most new ones are just occasional carry when I want to. the Cbob and PM45 have plenty of rounds through them so no worries.

Which reminds me I think I'll switch back to the Remington for a bit, love that gun too. Or maybe the Magnum Research 1911 G, course the Ruger's been neglected lately too.
So many guns, so little time.

[jocko]

no doubt 45 1911's requi8re alot of break in. 9mm sure don't. Just sayin didn't know u could actually count to 750 colonel. Thats good news..

[Bawanna]

Well I had help with the counting part. Way to make me look stoopid.