Originally Posted by Fastbolt

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The extractor and sear release lever are "fitted" parts, so even if you acquire them you'd still have to find a gunsmith familiar with S&W pistols to install them.

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The extractor and spring require the use of a force dial gauge for the spring tension, and a factory-provided armorers with a Go/No-Go Bar gauge to check for filing the extractor's adjustment pad to fit the extractor in any particular slide. (They used to use a Go/No-Go Flag gauge for checking another dimension behind the extractor hook, but eventually decided that it wasn't necessary, as long as the Bar gauge was used properly.)

There are optional extractor springs available, lighter/heavier than "standard", to compensate for any machining tolerance variations in the depth of the extractor spring hole, and the older 9's sometimes required a special repair extractor spring kit, which used a pair of nested springs (which was eventually replaced with just a couple of different strength single springs to try, to see which one worked better).

That all means that properly replacing an extractor and spring is probably beyond the knowledge, skills and tools of the average kitchen table tinkerers and enthusiasts.

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