Beretta ARX-100 Review in Videos 0 A long, no-nonsense look at the newest polymer semi-automatic rifle from Beretta, the ARX-100 in 5.56x45mm. Tweet Share +1 Email READ: 12-Gauge Ammo Test Segmented Slug Showdown: Hexolit 32 vs PDX1 ARX-100 Beretta 2014-10-19 Rich