American Spirit Arms Side charge upper?

[65Whelen]

Been looking at uppers lately and bought a forged Rainer, nice upper and fast shipping. Only advise I can offer is make sure it's 7075-T6 alum and not the 6061. I came across some billets that were relatively cheap and yup 6061 alum. If your going to invest in a billet might as well get a good one.

Some advise I got from the Horde, it helped me:
http://www.65grendel.com/forum/showthrea...ver-Advise