I have seen external extractors break their roll pins and the result was an extractor flying out of the gun with its spring. This cannot happen with the internal extractor. I have also seen guns with external extractors and solid retainer pins also loose the pin when it worked its way out the top of the slide with the same results, a lost extractor.
I think where most people get themselves into trouble with internal extractors is that they tend to drop a round in the chamber and then slam the slide shut which forces the internal extractor to snap over the loaded round. The extractor was not designed to be used in this way, rather it was designed to have a cartridge fed up out of the magazine. If used in this way the spring steel extractor may get out of adjustment and if it is made of a casting the casting will soon crack and break. If you like throwing one round into the chamber at a time by hand then the external extractor would be much better to have.
As was stated elsewhere the external extractor came into being because it was so much cheaper to make and fit to the gun with less labor.
I think where most people get themselves into trouble with internal extractors is that they tend to drop a round in the chamber and then slam the slide shut which forces the internal extractor to snap over the loaded round. The extractor was not designed to be used in this way, rather it was designed to have a cartridge fed up out of the magazine. If used in this way the spring steel extractor may get out of adjustment and if it is made of a casting the casting will soon crack and break. If you like throwing one round into the chamber at a time by hand then the external extractor would be much better to have.
As was stated elsewhere the external extractor came into being because it was so much cheaper to make and fit to the gun with less labor.