Let's start by saying that cheap sniper rifles need a ton of work straight out of the box..
Most of them come at ludicrous power but pretty much zero accuracy and consistency..
The gun itself isn't a bad base to start with, although upgrades may not be as easily obtainable as VSR parts..
First things first, get a consistent gun:
Eliminate any air leak, tear apart the gun and clean any excess grease (there will be plenty in Chinese guns), check the o-rings, replace them if needed..
To the hop chamber/nozzle, if there's any leak try to wrap a few layers of teflon tape, it does really work wonders!
Then check the hop rubber, check the nub and how everything lines up.. Clean up the barrel and check if it's straight..
If you're planning of putting a huge stiff af spring in there, replace the whole trigger box with something more durable like a zero trigger..
You may be wanting to look at the lrb barrel mod, a nice aluminum piston and a sorbo pad glued to the piston head to reduce noise.. Get a couple of barrel spacers to avoid unnecessary vibrations when firing..
Stuff the stock (where possible) and the void between the inner and outer barrel with foam to further reduce noise..
And for God's sake use the heaviest WHITE bbs you can find.. It's easier to compensate and to be fair people rarely look for that one bb.. And if they manage to spot you you've done something wrong to begin with
