Here are a couple of interesting little data points: the channel liner appears exactly once in the
Armorer's Manual (©GLOCK, 2009), in the
Exploded Drawing on page 13. There is no other mention of the part, no maintenance procedure including detail stripping, and no other mention of the channel liner tool (at least none that I could find after going through the manual twice). There are two mentions of inserting the firing pin assembly into the firing pin
channel cut, but no mention that there is a liner in that cut.
In the
GEN4 ARMORER'S MANUAL (©GLOCK, 2010) the channel liner is not pictured in the
Exploded Drawing on page 2, although it is included in the parts list. It is as if Glock didn't know the part is included in the Gen4 pistols (it is).
Looking a little further, there is no current Glock channel liner tool in the Armorer's parts list, but there is an aftermarket tool available through Brownells (
CHANNEL LINER TOOL for GLOCK® | Brownells). Glock does offer a
Channel Maintenance Kit, consisting of a special set of five scrapers designed to clean out carbon from various recesses in the slide. It's available from Glock and from MidwayUSA (
Glock Armorer's Channel Maintenance Kit).
Talk about a "stealth" part!
Chris