Even though this blog is dedicated to the rifle I do have a carbine laying about somewhere…
A little about the build and where it is going.
This carbine is pure frankengun. Sixteen inch mid-length Sabre Defense barrel, bushmaster lower and parts kit, Vltor modstock, LMT bolt group with enhanced bolt, and a Vicker’s sling.
Quality components allow this rifle to run like a sewing machine. When building an AR15 it is very important to do your research and purchase the best quality you can afford. This is especially true for a carbine. With anything less than a rifle length gas system you are dealing with pressures that the AR15 was not designed around. The carbine length gas system (and shorter gas systems) exhibit severe timing issues that compromise component life in the AR15. Moving up to mid-length or rifle-length gas systems should extend the life of your AR15 as well as improve reliability. A carbine length gas system simply begins the process of extraction far too early; as extraction begins the brass case has not yet reached a low enough pressure for it to “comfortably” slide out of the chamber. If you need heavy duty extractor springs and O rings to aid in case extraction something is not optimally set up in your rifle or carbine.
If you are going to be following this blog and are going to build a carbine instead of a rifle… please sport a mid-length system or longer. There is simply no practical reason to go shorter in a 16 inch carbine other than to create a M4 clone. Some people have carbines that run like the wind. I have owned a reliable carbine system myself, but once my eyes had been opened to the benefits of the mid-length I won’t be going back.
Lets not forget that longer sight radius either.