Originally Posted by ceazer
hey man i just got the king arms m4a1 looking to do a little mod on her n just wanted to know what u think would be good for it ie tightbore shimmed ect (internals) recommended by blue fish. gun is shooting constant 380 fps with .25s internally stock so far....... thanks ceazer
Got the PM. Tightbore and a gearbox rebuild (shimming, fitment and lube) would be best. Anything that needs to be replace for reliability or performance enhancements can be done then.