Kjw m4 piston cup
 

Stock pistons cup starting to ware out .
Any ideas if a guy should get another stock one or get a different brand ?
Any thoughts or ideas would be awesome. !

What is the big hype about the hop up rubber
If mine wears out Do i get a new stock one or buy a different brand of hop up rubber???

Im lost here any help would be sweet ?

Oh one more question when bolt wears out should a guy get another V2 bolt or the V1/2 bolt from cradel soft ?