buymoreammo wrote:perhaps masked gunmen kicking in my front door? or maybe tromping through the woods with a group of other patriots?
So basically you're looking for a rifle that you can use to take on organized police/military that may be wearing body armor in a fictional post-apocalyptic survival scenario a-la "Lights-Out", etc..
Focusing on the original topic and forgetting the whole patriot militia/defeating body armor bit...
Is the AR10 a standard platform that will interchange parts easily in an absence of commercial sources like the M1a? Which design has been truly battle proven in a variety of climates and conditions? I like the concept of the AR10 platform, primarily because I think highly of the .308 Winchester / 7.62 NATO cartridge... just not sure how it would hold up in the scenarios you are obviously considering, I haven't seen any really strong data sets on torture tests of the platform outside of a shooting range. Your best bet is to take the initiative and educate yourself using Google and get some trigger time on both platforms to make up your mind, then perhaps ask SPECIFIC questions based on your research and observations about the merits of each platform. The FN-FAL and H&K G91 are other solid 7.62 NATO battle rifles with a long history of military service that have not been mentioned but should bear consideration.
Short version - both good rifles, I prefer the ergonomics and operation of the AR platform rifle but, like me, most people giving you advice have already done their own homework to end up with an opinion on the matter. You'd probably get a better response if you offered some perspective of your own based on experience/research and then asked for opinions rather than jumping all over topics in the same thread from a generic "which is better" to defeating body armor and wandering in the woods in a patriot militia?