Lightweight Commander feed bobble

Does it do it with the factory magazine?

Ritchie said:

... Pachmeyer magazine ...

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How old is that magazine?

The case head is not sliding up the bolt face, like the cartridges before it. Bend the mag spring so the bullet nose is lower in the mag. Less pressure from the spring on the front of the follower.

My guess.

In my experience this usually is because the feed lips got out of parallel and lets the nose rotate up before the base clears the release point. Its most common on the last round because the follower helps tilt it up in front. I would squeeze the feed lips in a bit and see how it goes. If you go too far you won't be able to load it, or in less extreme cases you'll start hanging on the bottom of the barrel instead.

Ritchie said:

The mag used here is a few years old...

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Admittedly, time fly's when you're having fun, but I'd be surprised to hear there are Pachmayr stamped mags that were made in this century.

My bet is your feed lips have spread and it's time to look for a new mag.

I have a Combat Commander and a bunch of Colt and Chip McCormick shooting Star mags. Every so often I'll get a failure to feed with one of them, usually a nose dive into the mag well. On the advice of a friend I bought a couple Wilson Combat mags. Presto! Over 500 rounds so far with no feed problems.

Ritchie said:

The factory mag is a wannabe 8-rounder that has already proven marginal.

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then why are you trying to blame the gun?? toss it in the trash and buy quality mags..

there are usually do problems that lead to poor feeding in a 1911. As everyone else already stated, the biggest and most common are mags. I like wilson combat mags personally. chip has never really done me wrong either.
the second issue is if the extractor got bent tighter for some reason or its angle changes its deflection. on some 1911s the extractor needs to be retuned. if its not extractor related, i wouldnt mess with it if you arent familiar with how to. i have formal training with colts and it can take awhile to find good tension.
the other thing is 1911's are sensitive about hollow points as its coming up the throat, most modern today 1911s are throated to be able to except them, but still, theres that little space between the feed ramp and and the frame that the like to get hung up on and come up in weird angles, or not enough angle.
your bullet in the upward angle looks like its magazine related..the follower perhaps.

Walkalong said:

When made properly, rounds do not "ride up" the ramp on a 1911. At most, they merely glance off on their way to the chamber. If the "ramp" is at the correct angle, and in the right place, and the barrel entrance hasn't been screwed up, it will feed, hollow points included.

Most 1911 failures to feed are mag related.

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Agreed, my Norinco has the roughest feed ramp you could imagine. It has a lot of tooling marks running perpendicular to how some would think a bullet would "run up" the feed ramp.

But.

With good Checkmate or Chip McCormick shooting star mags, it'll feed everything from empty cases, HP's, FMJ's and SWC's. I wouldn't dream of polishing it. The correct geometry is more important than being super slick.

Ritchie said:

The CMC mag had nosedive problems. Bought brand new, never tinkered with.

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A common recommendation for new 1911 mags, especially 8 rounders like McCormick or Wilson 47D's is to load the mag up and let it sit for some time, a day or two or a week, or load and unload the mag over and over, to get the spring to "take a set".

Ritchie said:

Just to be clear, I no longer use the Ruger factory mag at all. My suspicion is that the lightweight frame combined with the extra velocity of the HST (890 FPS listed value) gives enough extra jolt to knock the last round loose. I will be testing several other factory loadings and some down-loaded HST rounds after I finish making the .45 puller collet. This pistol has run WW white box ball and some handloads with no problem, with the same mag. A brand new Chip McCormick 8 round mag has also been judged not suitable for actual use. I'm not blaming the gun, it just has...characteristics...of it's sort.

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As an FYI, this is a FAQ comment from Wilson Combat related to ammo selection for their Compact guns, but it may be applicable to your issue...

https://www.wilsoncombat.com/faqs/

All the mechanical changes are important, but the biggest factor is ammunition selection because it affects both slide cycle speed and the magazine’s ability to lift the cartridge into position for proper feeding. Ammunition loaded with 230gr bullets generate more recoil impulse (especially +P loads) than 185gr loads, and 7 rounds of 185gr ammunition weighs 315gr less than 7 rounds of 230gr ammunition, making the column of ammunition easier for the magazine spring to lift. I hope you see where I’m going here?

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