Easy slide release?

[zymurgeist]

OK, so how does it get the spent casing out of the chamber?

Newton's third law of motion.

In a semiautomatic weapon the extractor's function is to remove unfired shells and hold casings up against the breach face until the ejector hits it. Lack of an extractor can cause jams and stovepipes from the casing not ejecting properly but the casing won't stay in the chamber unless it's so stuck an extractor couldn't pull it out anyway.

 

[martybee]

Blow back system. Gas pressure blows the case out of the chamber!


Beretta 3032 Tomcat .32 ACP Simple blow back system.
There is no extractor. The gun is a a direct blow-back system. A portion of the expanding gas from firing is used to push the spent case out of the chamber. It seems to work effectively, but it can lead to jamming. The barrel is a Tip-up design so you can pry out the spent case in case that happens.

 

[CB3]

Blowback operation explained:

Blowback (firearms - Wikipedia)

Extractors and ejectors are reliability enhancers, especially with locking breech designs. However, it is always the rearward movement of the fired case under its own gas pressure (equal and opposite) that causes a locked breech to unlock. So, the principle of gas actuation for "extraction" works even with an extractor. In truth, the extractor only extracts when the case is stuck. It is more of a guide than a mechanical pulling force, as the case is blowing itself out of the chamber anyway. Where it enhances reliability is when it holds the rear of the case for the ejector to flip the case out of the ejection port, but even that is unnecessary as the next round feeding can kick out the spent case. If the extractor is broken and there is still a working ejector, the rearward travel of the spent case should impact the ejector before the next round rises enough to kick the spent case out of the way.

Blowback, non-extractor no-ejector systems are cheap to make, operate on simple principles, and may be less reliable than locking breech actions with other mechanical enhancements. However, losing an extractor or an ejector may not automatically disable the gun. That was my point.

As to the original claim that auto forwarding will break an extractor, I don't see how. The mag is loaded in the usual way, and the rim of the top round in the mag still slides through the extractor groove in the same way. If there is more force of the brass rim against the extractor than a soft insertion, I don't believe it is enough to "break" an extractor in a much shortened period of time. I don't mean to call the poster's friendly gunsmith a liar. I just don't understand how it would happen. The mag's upward travel to seating is stopped by the mag bottom plate, not the extractor. The amount of movement of the extractor when a rim slides under it is minimal, and it is typically a strong, forged part designed to handle the forces of recoil, which are far greater and faster than sliding a rim under it upon a forceful mag insertion. I don't worry about it.

 

[ggibson511960]

Unloading!

Blow back system. Gas pressure blows the case out of the chamber!


Beretta 3032 Tomcat .32 ACP Simple blow back system.
There is no extractor. The gun is a a direct blow-back system. A portion of the expanding gas from firing is used to push the spent case out of the chamber. It seems to work effectively, but it can lead to jamming. The barrel is a Tip-up design so you can pry out the spent case in case that happens.

The tip-up barrel feature on the Beretta family of blow-back auto pistols (Jetfire, Minx, Tomcat, etc.) is there primarily to unload the chamber. You could use it in the unlikely event of a stuck fired case. Eliminating the extractor makes these pocket pistols cheaper and more compact without sacrificing reliability. If the gun goes bang not much can stop the empty case from extracting itself.