Charlotte

Charlotte is a clone of an M16, model R604.  More specifically she's a clone of an early M16.  Why?  It's actually kind of an obscure variation.  It was made concurrently with the XM16E1 and M16A1 (both are model R603).  Both the M16 and XM16E1 were improvements on the model R602.  This is the rifle that the Air Force asked for without the forward assist the Army was demanding.

She has a partial fence lower receiver, 1:12 rifled barrel, three-prong flash-hider, chromed bolt carrier and no forward assist.  There's no chrome lining the bore, just the chamber.

The early model R604 was made before combat experience showed more improvement could be made, experience that mark the differences between the XM16E1 and M16A1.

Although the three-prong flash-hider does a better job of suppressing the flash than the later birdcage; the prongs do get snagged on things.  I notice that Smith Industries with their Vortex has reintroduced the open prongs and rediscovered that it's better at hiding the flash.

The chrome bolt was expensive to make and the shiny surface could give a soldier away.

The partial fence lower gave way to the full fence lower with a ridge surrounding the magazine release to help prevent accidentally dropping the mag.

These changes were incorporated into late production M16's in the early seventies about five years after they were added to the M16A1.  The very first guns were issued without any chrome in either the chamber or the barrel and the chrome found its way into the R604 as the change was made to the R603.

In addition to the forward assist, the Air Force never adopted the storage compartment in the buttstock.

Charlotte is a collection of vintage surplus parts with the exception of the lower receiver and trigger group.

Additional build notes here.