I’d like to start by stating that this was my first attempt at tuning an air rifle. I used a combination of guides found online from various sources including Charlie da tuna and information from several air gun discussion groups. I decided to make a guide specifically for the Crosman Phantom 500 .22 cal air rifle since there were none to be found at this time.
That said if you take it slow and work methodically you should be able to achieve successful results.
Now onto the tear down.
1: Remove the 2 forward stock screws and washers.
2: Remove the 1 screw behind the trigger.
3: Remove the receiver from the stock.
4: Break the barrel free but do not cock it! Remove the barrel block pivot bolt to separate it from the receiver forks.
6: Next you have to unhook the sliding block spring from the trigger block. Unhook it at the front leaving it hooked at the back on the trigger block. You can now remove the e clip as well.
Then punch out the lock pin with a wooden dowel or a screw driver and a mallet. Once the pin is out while still retaining pressure on the receiver, pull out the dowel or screwdriver now in the hole. Slowly back off the pressure as the spring pushes out the end cap. Voila!
Similarly when putting it all back together you can try to do it the same way without a compressor just in reverse order. However putting it back is a little more difficult as you have to line it up right and put the lock pin back in. If you decide to put in a new stronger spring it will prove even more difficult without a compressor. It is your choice how you proceed.
9:Now you can remove the rear spring guide followed by the spring.
11:Take the tophat off then pull the piston out using a screwdriver thru the slot of the receiver. My tophat did not fall out on its own. Seems there was some corrosion keeping it stuck in the piston. I sanded her down smooth before reassembly. (the above diagram is taken from a web source)