No Restriction– The majority of parts are sold over the counter. They may require minor and
skilled fitting. This is especially true on older guns where parts were hand
fitted during assembly as labour was cheap. Later, tolerances were improved
with modern manufacturing equipment and processes.
Gunsmith Restriction – These parts are considered to pose liability or
fitting concerns such as triggers, sears, safeties and breech bolts for
example. There are parts that come very rough and require qualified fitting.
Manufacturers deal with these
parts in different ways and the bottom line is the liability transfers to the
gunsmith installing the part. This usually means the gunsmith must be fully
licensed and have adequate liability insurance coverage.
Factory Only Restriction – Part is factory only. These parts are not sold. They
are for factory replacement only and the gun must be returned to the factory
for repair or to an established ARC (Authorized Repair Center).