thanks .. yeah it is.. i really like it and cherish the rifle as it was a gift from PSA to help motivate me to keep fighting the cancer so i can keep shooting it. 
its a lot of fun to shoot..that trigger is amazing.
as for the ARV i have.. well i built it to be like a mini mp5 almost but on an ar platform obviously..
here it is.
An uber-accurate Jam-O-Matic isn’t much help.
I’m going to say that looks like an Odin Works Super Lite barrel?
The guy that built this says it’s actually closer to a 5-inch barrel, and he installed the shroud to get it to legal length. The theory, apparently, is that the lightened front of the carbine (aluminum tube vs steel barrel) will be easier to swing from plate to plate.
Not hard to build, can be difficult to get running perfectly, especially for competition. That’s all.
As you said assembly is not too tough, but normally you will have to juggle spring weight and buffer weight to assure proper ejection and timing. Once done, they are extremely reliable.
Feed ramp?
