need help converting my g&g m4 gr-16 to a cqb

[FearlesFred]

I have a two tone g&G Gr-16 w/blow back and want to make it into a cqb version with the extra barrel length hidden by a silencer. Can i just buy a short outer barrel (e.g. dboys), some front irons and silencer or is more required? any help would be great.

A side note is i want 1 ris rail to go underneath my M4 foregrip but can't find any. Help please

 

[MiloXC3]

I'm not answering your question unfortunately, but how does the G&G M4A1 perform? I don't know whether to get the SRC M4A1 or the G&G M4A1. Contact G&G and see if they know of any RIS rails that fit.