we've upgraded 4 different guns from 4 different brands, and we are very confident.
A&K SVD- upgraded to m150 spring, upgraded hop up unit and nub
JG m4a1- upgraded barrel, hop up bucking
CA M4 sportline- added high torque motor, tightbore barrel, bucking, nub, metal bushings and spring guide, m120 spring, shimmed and lubed
G&G M16- swapped out stripped piston, super high torque motor, m130 spring, silent piston head, ball bearing guide, ball bearings
also, we use the websites discount code system to make sure you save even more money.
last but not least, we can do an upgrade to your guns range and accuracy: tightbore barrel, bucking/nub upgrade. labor is only 10$ for that.