I'm starting my first build. I bought a Franklin Armory complete lower and I just ordered a 20inch gun kit from Rguns. They said it would take 4 weeks to recieve the parts after I purchased it. There wasn't alot of information on this kit. It doesn't even give the rifling twist on the barrel. But this is my first build so I didn't want to go all out with expensive parts. I figured with the prices coming down I can upgrade the upper laterand all I would have to do is buy an inexpensive lower reciever to put these parts on and have another gun to tinker with. Has anyone bought a gun kit from Rguns and does anyone have a clue what the rifling might be on a 20 inch barrel.