by xandman » Mon Jan 09, 2012 9:27 pm
Yes you can, last time I upgraded a "G4" it was just a G&G CM. I got it past 4 with out any issues. (Echo Max piston, madbull 130 spring, madbull spring guide)
Friendly neighborhood armorer
Leader of team "yakuza"
å¿ èª å¿ƒ , å誉 , å°Šé‡ , æ£ç¾© , 勇敢 , 慈悲
Irene VI, Irene VII (squad leader), Northern wind V, Northern wind VI(squad leader)
Remember " Big D" "1978-2009"