Slide Locks Back on Kimber with Ammunition Still in the Magazine

From: Steven P. Schaufler

Well, I put about two hundred rounds through my new Kimber Compact CDP pistol this afternoon. I found it to be quite accurate, shot to point of aim, and was very comfortable shooting. This Commander sized pistol, my first, just “feels right” and seems much better balanced than my Defender. I did run into one problem though. In firing the approx. two hundred rounds I experienced three stoppages, all related to the fact that the slide stop engaged while the magazine still had rounds in it. I know some advised me that they had, with their Kimber Combat Carrys, trouble in that the slide stop failed to engage at all, I’m not having that problem at all, but just the opposite. If anyone can tell me the cause or possible cause for this and a solution, I’d be much obliged. Thanks.

From: Syd

Steven, I was having this problem occasionally with my Compact. I replaced the slide stop with a Wilson “Bullet Proof” slide stop and it hasn’t happened since.

From: Paul Schwenke

The cause of the problem is usually do to the nose of the bullet (large diameter nosed like the 230 Ball or hollowpoints) bumping against the slide release and engaging it. The other possible solution is do to your left hand bumping the slide release. I have had both happen on different guns.

The first reason is why my hybrid pin gun is filed and smoothed so the slide release doesn’t work at all. Using large 255gr SWC made for 45 long colts hit the slide release very often. More losses occur do to this problem than any other I know of. Some guys think it is their shooting style rather than bullet shape. You file the area where it engages the magazine lip for proper function. Try shooting 200 grain SWC in the gun to see if the malfunctions go away.

Carefully take off or smooth the area of the slide release which touches the magazine lip until the problem goes away or bring it to a gunsmith. If you have dummy rounds put them in a magazine. Take the gun and make the slide be held back by the slide release, carefully put in the mag of dummy rounds, and watch what area of the bullet hits the slide release. Do minor adjustments to the slide release then after. Some of the 230 Ball ammo or equivalents has different shaped ogives on the bullet. This causes problems on many guns. Another He shouldn’t charge very much.

From: Paul Schwenke

Kudos to Paul for his timely AND correct advice. Following it, I discovered that if the rounds were correctly positioned in the magazine with the back of the cartridge firmly against the back of the magazine there was no contact between the bullet and the slide stop. However, if the bullet had moved forward, even as little as an 1/8 of an inch while in the magazine (which, as we all know, commonly happens under recoil, particularly to the last few rounds in the magazine when the spring strength is at it’s weakest) then the bullet DID make contact with the slide stop and lifted it up as it (the bullet) rose into position to be chambered (this would also explain why it didn’t occur every time and only after the first few rounds had been fired). I found, at least on this slide stop, that there was a big leeway between the amount of metal that was contacting the bullets as compared to the amount needed to reliably contact the magazine follower. Seeing this, I filed off the metal at the contact point till it no longer touched, even in a worse case scenario, with the bullet well forward of the back of the magazine. I’ve yet to actually test this fix, but am confident that the problem has been cured. Time at the range tomorrow will tell the tale. Thanks again, Paul, for the help.

I must add that I feel good about being able to fix the problem, but I don’t feel quite so good knowing that my Kimber is the most expensive 1911 I’ve ever purchased and also the only one I’ve ever had to work on to get to reliably shoot hardball. All my other 1911s were Colts and they shot reliably right out of the box. My Defender DID have a last round jamming problem, but it was magazine related. No knock on Kimber, because this is also the most accurate 1911 type I’ve owned and the workmanship on it is obvious, but just a simple statement of fact.

From: Wayne Smith

Hope you got it fixed, Steven. Now, be aware that some followers move left to right, also. If you filed off enough of the tab, you may find that some mags won’t lock up on empty, some of the time.

From: Syd

I think Paul’s diagnosis is correct, that of the bullet bumping the slide stop, and if you’re comfortable with trimming it yourself, I am pretty sure that the fix will work. My Compact is my match gun and I noticed that the MIM slide stop had gotten beaten up, so it seemed that the replacement was the way to go in my situation. Also, mine didn’t lock back prematurely when it was new. It was only after about 4,000 rounds that I began to have the trouble.

From: Don Blaufuss

Steve: Before you start grinding and replacing, I had the same problem with a new full size Para-Ordnance limited, called the factory and they said its an inertia problem. They fix it by putting a small dimple on the slide stop where the plunger contacts the slide stop. They wanted me to send it to the factory but I didn’t want to have it gone for 2 months so i used a small drill bit and put the dimple in myself. You don’t need a big crater or a hole, just enough for the plunger to have something to work with. Worked for me.

From: “Mike Fairleigh”

I did experience the “slide locked open with rounds in the magazine” syndrome twice, however – once with the factory POS Shooting Star mag, and once with one of my Wilson Combat mags. Both were with Win 230 gr. ball. It seemed clear that the next round in the mag was just brushing the slide stop up. I know this was discussed here not long ago; what was the final consensus as to the fix? Stone the stop? I’m concerned about removing too much. Replace it? Thanks for any input.

From: Steven P. Schaufler

Hi Mike. I’ve performed this operation twice within the last few weeks, most recently a few days ago. First let me say, and I’m sure you’re already aware of this, it has nothing to do with the brand of magazine, but rather the fact that you were shooting hardball. The hardball bullets are ever so slightly longer than most hollowpoints and when the cartridges get pushed up a tad in the magazine from the recoiling of the pistol they contact the slide stop as they are pushed up and, of course, the slide stop locks back and you have a stoppage. The fix is pretty easy and is a relatively safe procedure. Before I go on, I’d suggest you call Kimber, tell them about your slide stop problem and have them send you a replacement which they will cheerfully do. Chances are it will be exactly like the one you have, but it can act as a backup in case you DO remove too much metal, as unlikely as that possibility may be.

Now to the fix. What I did was I first removed the slide from the frame and inserted the slide stop into position as if the pistol were assembled. Then I took one of my magazines, loaded a hardball cartridge into it, then pushed the cartridge forward as far as possible while still being able to keep it under the lips of the magazine and still at the normal angle. Then I inserted the magazine into the mag well and slowly pushed the magazine upward. When the cartridge got to the point where it was at the level of the slide stop, I noted exactly where the bullet head was engaging the stop (you can also do this with an empty mag and you’ll see that there is much more metal engaging the magazine follower than there is causing interference with the bullets, so there is very little chance of you removing too much metal). Now just remove the slide stop from the frame and remembering the area where it was touching the bullet head, start filing. In the case of my two, it was along that rear edge, the edge closest to the magazine well, and that point or angle where that edge and the forward edge meet. Good luck and tell us how you make out. I’m sure you’ll have no problems with it.

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