Just behind the extractor hook is a pad on the extractor body that positions it and determines contact of the extractor groove
with the cartridge.
The semi-rim rests in the extractor groove
of the underlying round, and in order to move the top round forward, it has to push all the underlying rounds deeper into the magazine under all that magazine spring pressure.
Cases can be formed from the .32 Long by removing the rim, cutting an extractor groove
and sizing and trimming.
All feeding must be from the magazine and the extractor claw rides in the case's extractor groove
starting at the time the cartridge moves upward out of the magazine.
Rim diameter is 0.407 inch and case body ahead of the extractor groove
is 0.375 inch.
All that remains now is to cut the extractor groove
in the rear of the barrel.
4 rimless cartridge requires small pawls to reach into the extractor groove
remove the case.
Keep an eye out for that telltale bright, shiny ring in front of the extractor groove
that indicates an incipient head separation.
According to NAA, "Behind the neck, all case dimensions and configurations, including the extractor groove
, rimless case, cartridge diameter and bolt-face engagement are identical to the .380 ACP.
Check cases for any flaws such as a too-battered extractor groove
and discard any that don't look right.
The Groove Smooth is located on the outside of the Chambered Reference and is used to identify the cylindrical runout of the re-sized brass and the trueness of the extractor groove
, and also to ensure the groove is free of any defects or obstructions.
A cartridge case may rupture into the extractor groove
in extreme cases.