That's pretty widely known, TP.AR stands for Armalite (big misconception about the AR term)
Actually, the real Armalite was the small arms division of Fairchild Aviation. It's a shame they're out of business. At least they did sell the production and name rights of the AR-15 to Colt back in the 1960s. Otherwise, no real AR rifles would be available today. As far as AR-10s, there's a company in Illinois calling themselves Armalite now. They make some rifles they call AR-10s, but those new fake AR-10s wont even use the same magazines as the real Fairchild Armalite AR-10s used. The DPMS LR-308, and Knights SR-25 & M110 are built on the real AR-10 platform. In the case of the Knights rifles it's probably because Eugene Stoner, the man who designed the real AR-10, went to work for them after he left Armalite.just to add...any other .308 on an AR platform is not an AR10, only Armalites can say that...the others are just high price rifles on that platform.
MOD (UK) has adopted the LMT. US Army has adopted the Knights M110.Personally, I like my military pattern rifles to actually have made it thru military trials.