The SAM7SFK-80 rifle is a semi-auto version of the Bulgarian model AR-M4SF with the NEW Arsenal Gambit attached which extends the barrel and enhances the firearm. From the right side folding tubular Buttstock to the vertical Front sight / gas block combination this is truly an authentic Bulgarian rifle. - caliber: 7.62x39 mm - total length: 908 mm/35.75 in - barrel length: 411 mm/16.2 in - twist rate: 1 in 240 mm/9.45 in - weight w/o magazine: 3.44kg/7.6 in - muzzle velocity: 710 m/s/2329 fps - effective range: 500 m / 547 yds - maximum range: 1100 m / 1203 yds - rear sight range: 500 m / 547 yds - rate of Fire: 40 rds/min