I'm new to the forum and thought I'd get the first post out of the way. I'm currently building a 224 Valkyrie caliber AR-15. I'm in a bind because I'm trying to figure out the best buffer set up to use. I'm getting the Magpul ubr gen 2 stock which allows you to use either a carbine or A5 length buffer set up with it. I've got a rifle length gas system on my barrel without an adjustable block. Anybody have some advise for me??