I have never seen where the US military has ever bought the AR-7 in any numbers. I believe some of the early Armalite AR-7's were bought and tested, but I'm not aware of either ever being adopted. I have never seen one stamped US Property. The M4 and M6 were both bought and used in far greater numbers than the AR-5. I have never seen an AR-5 in civilian hands, which makes me think there weren't many produced. As slick as the AR-7's are, they were never bought by the US Military.
Specifically Survival Arms is two companies removed from the timeframe that the AR-7 was evaluated. So it's a commercial product, that was sold commercially and it was never used by the military.
