My experience with the AR 7.62x39 was lengthy, many got it close in their attempts, most failed and hogged out the entry point of the round into barrel when the problem was the magazine. The ejection problems were often overblown or Over Gassed. This maker list the spec of the gas port. Now I do not have this makers product but should I find the $$ I believe this to be a good choice. Bear Creek Arsenal 16" 7.62x39mm Heavy Contour 1:10 Carbine 41V50 Barrel - Parkerized SKU: B762CHB16110-P Manufactured by Bear Creek Arsenal 1 Reviews On Sale $39.99 Regular priced @$79.99 In Stock NOTE: Limit 1 per household. Quantities exceeding 1 will not allow checkout. Details This high quality Bear Creek Arsenal barrel goes through its entire production life in Sanford, North Carolina at Bear Creek's facilities. Drilling, reaming, rifling, and turning are all accomplished on their CNC machines under ISO-9002 Quality Systems, allowing Bear Creek to put every barrel through a 100% inspection and air gauging process, ensuring every individual barrel is flawless before it leaves their facilities. This 16", 1:10 twist, heavy contour barrel is machined from 41V50 chromoly vanadium steel, heat treated to RC 28-32 hardness, and properly stress relieved with a durable parkerized finish. Chambered for the inexpensive 7.62x39mm, BCA expects that it, along with any of their barrels 16" or longer, will hold a 1.000 MOA group at 100 yards when used with appropriate ammo and shooting techniques. Gas Port: Carbine, 0.093" Specifications Barrel CoatingParkerized Barrel ContourHeavy Barrel Length16 Barrel Material41V50 Chrome Moly Vanadium Steel BrandBear Creek Arsenal Caliber Gauge7.62X39mm Feed RampsM4 Gas Seat Diameter.750 Gas System LengthCarbine Manufacturer.Bear Creek Arsenal PlatformAR-15 Thread Pattern5/8 X 24 Twist Rate1:10 One review 12/21/2017 6:57 pm Great inexpensive barrel. by Thomas I have this barrel in a complete BCA upper and without load workup it shoots both Varmageddon and Hornady SP .310 bullets easily into 1.25 MOA with just a 3X PA Prism Scope for 7.62x39/300 BO. Btw only using a front rest too. 1 MOA is certainly possible with load workup.