Last year, I started Project Icarus: to design a very accurate, ultralight AR15 using off the shelf parts.  My goal was a sub-6lb rifle, with the suppressor and optic included in that weight and I wanted to keep the parts as durable as possible, so I shied away from the use of plastic receivers.  Since off the shelf parts are designed to be strong and light already, I didn’t do any drilling, skeletonizing or anything to further reduce the weight.

At the end of version 1.0’s build, I had an AR15 that weighed in at a svelte 5.776, with suppressor and optic included.  While I had achieved my goal, I felt there was still too much weight up front that I could cut.  There was steel where titanium could replace it, there was aluminum where 2055 Li-Al alloy could be.  Taking the rifle back to the butchers block, I made the following changes.  As I’ve covered many of these parts in my previous build articles on the upper and the lower, the most detail will be dedicated to new parts.