Okay... last one. This one also came under my notice about 2 years or so ago... A stainless Colt XSE Combat Commander. One of the better ones that I've seen. So much so, that I eventually bought the gun.
For the first 1000 rounds or so, it was flawless, and the owner had a happy face everywhere he went. The problem started suddenly, and had me stumped for a week.
Evidence of short-cycle malfunctions on with an occasional stovepipe failure to eject. Bolt-Over Base feeds on the last round on nearly every magazine. Occasionally one the next-to-last round. Wolff springs had no effect. A lighter recoil spring had no effect. An 18-pound recoil spring made it worse. The gun passed the gravity test with flying colors, and would nearly chamber a round under gravity alone. Feeding was flawless, except for the Bolt-Over stoppages. There was never a failure to extract, and no other malfunctions were evident. On the occasions that the gun fed the last round, the magazine locked the slide on empty with only one failure to lock.
The slide to frame fit was excellent, with a tiny bit of side play and none in the vertical plane when the rails had a little oil in them.
Extractor tension was perfect, and the ejector was tight and undamaged.
The recoil spring was OEM, and tested at 16 pounds even. There was no coil bind in the spring. There was no interference between the barrel bushing and front lug. There was no interference between spring plug and guide rod...on the side or the head.
All magazines tested good in other guns, and were flawless in the XSE prior to the onset of the problem.
Once it started, the problem never got worse, with any stoppages occurring at about the same rate of frequency.
I never saw what the problem was... and if Kelie hadn't come down to the shop to ask me for money to go to the grocery store, I probably would never have seen it, even though I had examined the gun under a strong light with a loupe for any hint of what the problem could be. She spotted it, and I couldn't fix it. It was returned to Colt for the repair under warranty.
Well... Kelie spotted it, so I'm guessing it's an external problem.
You couldn't fix it, so I'm presuming it was a pretty big defect.
My guess -- the mag release was broached a bit off, thus keeping the magazine in the wrong position -- I'm guessing not quite in far enough.
Kelie noticed the mag wasn't fitting flush, which your examination didn't reveal because you were examining it unloaded without a mag.
Slide stop hole a hair low in the frame ?
I'm going to have to agree with Kaylee that is sound's like a magazine catch issue. But if you couldn't fix it by just replacing parts then maybe something in the frame wore out of spec making the magazines ride low or put the mag release at an angle?
And now you've given rise to a little riddle...
The defect was a major one... but it was small in size, and thus hidden from my searching, prying eyes. (A "Little Big" defect.)
It was an internal defect that was only visible from the outside.
Take the gun apart, and it was hidden from view... no matter how hard I tried.
The defect was visible only from certain angles. If Kelie had been standing 6 inches on either side of where she WAS standing, she wouldn't have seen it.
It didn't have anything to do with the magazine... magazine catch... or the slidestop or its location.
Good answer on the mag not fitting flush though... Seen that one cause a similar problem on occasion.
Remember that the problem started suddenly after the gun had functioned perfectly for 1000 rounds.
The Snowman said:
It's no fair. We can't LOOK at the gun.
ROFL... I looked at it 'til I went blind and didn't see it.
Imagine how humbled was I when my other half walked in and spotted it in three seconds...
Nope... Not a spec issue, and not the frame.
.45auto said:
Hairline crack on the slide
BINGO! Not in the port, though...
The crack was in the front part of the bushing's lug recess. I was wrackin' by pea-sized brain and rackin' that Evil Stainless slide, when Kelie walked in. About the third cycle, she said: "Is that supposed to do that?" "Is what supposed to do what? "Lemme see it" "Okay"
I handed her the gun and she pulled the slide back. I saw the front of the bushing move sideways ever-so-slightly. I took the gun and started rackin' the slide and on the fourth or fifth try... I saw the slide flex. Less than a half- inch forward of full travel, it sprung back and looked normal.
I took the gun apart and used a Mini-Maglight and a loupe... Couldn't see a thing wrong. The recess wasn't damaged. The bushing lug wasn't damaged. The slide looked fine. The bushing looked fine.
I looked hard at the barrel. No sign of binding with the bushing. No sign of the bushing ID binding with the barrel. The slide flexed less than .040 inch..about the thickness of 8 sheets of typing paper...but it was enough to cause a short-stroke in recoil, no doubt due to the springing action of the steel.
The slide was picking up every round except the last round in the magazine... so evidently it was just barely making it past the rims.
Now... as to exactly what broke the slide.
Careful measuring revealed that the recoil spring was a little less than one coil too long... about .040 inch. There was no APPARENT indication of coil bind because during the check, the crack would open up and let the slide hit the guide rod head... so there was NO coil bind during the examination, but there HAD been before I saw the gun. I figure that the slide cracked early on... probably within the first 25 or 30 rounds... or possibly even on the very first round, which explains why there was no damage to the bushing lug or its recess. As the gun was fired, the crack slowly progressed until it was long enough to start opening... but not enough to completely break the slide. There was enough spring in the steel to completely close it as soon as the tension from the recoil spring was off the bushing... and since it was hiding behind the corner of the lug recess... there was no way to see it. I sat there racking the slide, watching it happen... and the corner right in front of the recess let go. It probably would have broken clean off if he had fired the gun another 5 rounds.
I boxed up the slide and sent it to Colt. One phone call and 10 days later, I had a new slide back... complete a new barrel and all internals... and a new bushing. It fit perfectly. The back of the slide aligned with the frame, and all was well, except for one little nit-pick issue... The bushing was GM- length. I stuck it on a mandrel, faced it off to length and called the owner. About a month later, the gun was for sale or trade. Seems that he just didn't trust it. I knocked a home run on that one, and it now resides in my safe... and sometimes my holster. Function has been perfect, and accuracy is better than I can prove from offhand. Happy!
Yep... I upgraded the MIM sear and disconnect.
It's the dagnabbed LITTLE things that getcha!