Here is my observation on this rifle. It uses a VSR bucking and AK type rotary hop up unit, all metal. To remove the outer barrel, there is a hidden set screw under the rear flip up sight. Review the assembly and disassembly by James on youtube. It disassembles like the real steel version, and the trigger unit is very sturdy; unlike the unit on the WE M14. With .20 bbs, it was chronoing around 560 fps with propane. Valve is the now standard open bolt type. It shoots hard and fast, but be sure to do a couple things before skirmishing and when you get it right out of the box. If you buy this, ch
