as long as it has one 3-way set screw it will stay in place
cocker timing takes a while but it is pretty basic, its just adjusting rods and such until it shoots perfectly(its easier if its sitting right in front of you), search for websites(i think ravi's talks about it) on how to do this for more detail
Note:little hole on top of body is important
I find cockers are as basic as mags once you understand them
-Minimag Body HR
-Retro Valve
-Z grip with extender
-12V X-Boarded Revvy
-6 barrels including:10 Inch DYE SS, 8 inch Steel Wind, 8 inch stock minimag barrel, 12 inch BOA barrel, 12 inch Lapco Autospirit, 16 inch SPAA
-68/3000 Flatline