I've got two of those pistols. One off amazon and one from the flea market. They're S2-1's according to the SAG catalog. The .177 averages 316.09 fps.(high351.4/low276.2). The .22 240.1(high 249.4/low220.5). Big spreads. At first at 21 meters I could hit a sheet of copy paper more times than not. With a little practise and sight adjustment off a rest they would shoot 3-4" groups with a couple of flyers now and then. Take care, that front sight will cut you.
John, when you bend the barrel read the barrel bending in the tricks &tips gate first. Little steps at first. The jig is easy to build.Bill, Wal-mart chrony $85, free shipping. It's a simple one, you got to do the math.