I was having ejection issues with my 1911 (stovepiping on some mags with stiff springs and on the second to last round. Also same issue on very chewed up snap caps but not fresh) and I thought it was an extractor issue.
This is a bit of a daunting thing as extractors are a bit of a pain to remove, and to replace you need a gunsmith or to file your own retaining notch into the extractor pin.
But I found that my 4in 1911 did not have this problem. So I decided on a swap.
To do this I needed a thin drift to push the retaining pin out of the frame to allow the removal of the extractor from the frame. I went to the hardware store to get some tools, specifically a thin drift, some small files, and a punch.
Then I found the drift was too big, so I spend the evening filing it down until it was small enough. That was fun making a new tool but time consuming.
Finally, I got to removing both extractors... swapped them and... the problem did not swap.
So... it wasn't the ejector. This confused me for a bit. Looking at what it could be I was dumfounded, the problem could be narrowed to a few types of cartridges and was magazine independent.
Thinking I wondered if it was the extractor. That seemed not likely, but it was all that was left. A bit on the difference: The extractor grabs the end of the cartridge and pulls it out of the chamber of the barrel. This pulls the cartridge until it hits the ejector flinging it out of the gun.
Here's the twisted part, the extractor is trivially easy to remove. You take out a retaining plate that holds the firing pin assembly in, and the extractor slides straight out.
And... it turns out it was the extractor, despite the to parts looking nearly identical to my eye. But the extractor is a spring based part and does get worn out.
So, let that be a lesson to all your amateur gunsmithing. Be safe, be careful, don't force parts, and sometimes the problem can be something you didn't think of so it pays to be patient and methodical.