01-13-2014, 01:54 AM
Extractors and bolts are usually made by different types of machine shops, since they are different core competencies with regard to materials sourcing, machining, and heat-treating.
The best scenario is when you have one final company doing TQM on components before they go into a rifle or upper, and this starts with that single company soliciting the various machine/heat treatment/finishing shops with a specific set of technical drawings and data packages that follow a well-engineered scheme.
It is very rare that these individualized machine shops ever want their names known outside of the manufacturing chains, and once a regular manufacturer secures long-term work with them, that manufacturer doesn't want anyone knowing who their sources are because of competition.
Extractors are usually MIM'd, but not all of them. As to an extractor dragging inside the hard chromed carrier, the chrome will usually win.
You should feel resistance from the gas rings once they transition from the largest ID of the bolt channel in the carrier, to the mid-section ID where the gas rings are compressed into the tighter ID in order to provide a gas seal, combined with the bolt tail in the smallest ID:
![[Image: AR15BCG.jpg]](http://i1085.photobucket.com/albums/j422/LRRPF52/AR15BCG.jpg)
The best scenario is when you have one final company doing TQM on components before they go into a rifle or upper, and this starts with that single company soliciting the various machine/heat treatment/finishing shops with a specific set of technical drawings and data packages that follow a well-engineered scheme.
It is very rare that these individualized machine shops ever want their names known outside of the manufacturing chains, and once a regular manufacturer secures long-term work with them, that manufacturer doesn't want anyone knowing who their sources are because of competition.
Extractors are usually MIM'd, but not all of them. As to an extractor dragging inside the hard chromed carrier, the chrome will usually win.
You should feel resistance from the gas rings once they transition from the largest ID of the bolt channel in the carrier, to the mid-section ID where the gas rings are compressed into the tighter ID in order to provide a gas seal, combined with the bolt tail in the smallest ID: