Idk what barrel they use, but i severely miss my gen1 Rainstorm .177. The trigger was horrible at 4.5 lbs, but it was a damn tack driver and almost 40fpe with 21g slugs. On a calm day, moa with 13g kOs going 1050. I also took a 150lb boar from 50yds with it. 50yd limit with the 21g piledrivers...