So I picked one of these up the other day for $789 delivered. I thought this was a smoking deal and considering they have been discontinued, I figured if I wanted one I had better jump on it now before they are gone completely. I have read most of the 50+ pages of the RPR thread here but frankly, not much of it applies to the 5.56. Perhaps most doesnt need to because of cross compatibility. Understandably most are either 6.5, .308 or now 6mm. Doesnt seem many folks opted for the 5.56 and I guess thats why they discontinued them. Obviously the gun is Gen 2 since it was dropped before the gen 3 release. My question is about magazines. It did come with 2 factory Ruger mags. I am confused as to other compatibility. The owners manual that came with the gun is silent on the factory mags but suggests the use of PMAGS and AICS SA mags, even including pictures of them. How can a .308 case mag hold and feed 5.56 cases?? The RPR lower seems about the right size for a PMAG but.... Aside from factory Ruger, do any other mags work with the RPR 5.56??