Commander FTFs: last round loads in front of extractor

[moredes]

I have a newly delivered Commander that fails to properly load the last round from several magazines. I've used the mags in two other Commanders without any problems, but in this Commander, the last round chambers 'completely' except that it loads in front of the extractor.

I know this probably means the magazine springs are bad, but I've never seen this kind of FTF--especially on a last-round malfunction--every other bad-magazine malfunction I've ever seen has been a stovepipe or 3-point.

I'll try new mag springs of course, but can someone explain what's happening to cause this kind of FTF? is this what's called a 'nose-dive' FTF (obviously, I don't know what a 'nose-dive' looks like)?

Thank you.

 

[dfariswheel]

What's often going on is, either the vibration of the recoiling slide is jarring the round out of the magazine, or the round is popping up out of the magazine as the slide hits the cartridge as it's closing.

In either case, the round is laying loose on the magazine follower and the slide is simply pushing it into the chamber.
However, since the 1911 extractor is not intended to snap over the rim of a chambered round, the extractor is preventing the slid from closing fully.

Result: A live round fully chambered, the extractor behind the case rim, and the slide not fully closed.
Usual culprit: A bad magazine.

 

[Oro]

I've used the mags in two other Commanders without any problems, but in this Commander, the last round chambers 'completely' except that it loads in front of the extractor.

I agree with dfariswheel. Just because a mag works ok in one gun doesn't mean it's 100% good to go. It sounds like the magazine is loosing control of the cartidge as the slide is going forward, just as he described.

I would replace the magazine spring with a new high-quality one.

 

[moredes]

Thanks very much for your replies!