Sometimes, it's good to see how individual parts all fit together. Today we have a finished lower receiver which was completed with the CMMG lower parts kit and receiver stock extension reviewed here previously. While I am reluctant to delve into the realm so assiduously handled by my colleague, here's a quick run-down of how even a neophyte can complete an AR-15 lower receiver.
Installation of the parts kit was quite simple, even though this was the first time I had sat down and actually put a lower receiver together. Between the graphic depiction on CMMG's website and the excellent Brownells series on AR builds, it took less than an hour to put this all together (and I work very slowly when unsure of what I'm doing, as I've gotten to the end of more than one project only to realize I put something in backwards) with minimal fuss. The Gunner's Mount from Present Arms held everything together while in progress, and specialized tools were provided by Brownells as well.
The proof, of course, is in the execution: with a complete upper from Bravo Company (that had previously been broken in on another lower completed by York Arms), the now-finished CMMG-parts-equipped lower functioned flawlessly—and the stock CMMG trigger is actually pretty decent as far as stock triggers go. Right now the BCM upper and CMMG-finished lower are together in an "M4gery" configuration, with 16-inch barrel and Mil Spec stock, pistol grip, handguard, A2 front sight and removable carry handle.
The management reserves the right to change configuration without notice and at personal whim...