G&G GR16 Exterior Modification

I was thinking about getting a M16 length Daniel Defense free float rail for my M4A1, and also getting a full stock. I am in hopes that doing this will give me the "CQB M16" look. Kind of a best-of-both-worlds deal. Range + ability for CQB + a unique look. The only problem I have right now is figuring out whether or not the rail will fit on my M4. Any help/feedback on the idea is appreciated. Thanks! I have included an image from PimpMyGun

just so long as it won't end past the barrel... otherwise check with airsoftGI they should have some advice

Does your M4 have a delta ring?

Yes it does

That design you have would work best with a freefloat system. If you plan to keep the delta ring assembly you'll also need a front sight. Which is fine, it will preserve a lot of the 'M16' look.

I would love to use a free float system, but I have no idea how they work. I do not like front sights because I use an EOTech, and the front sight gets in the way, although, i may attach BUIS to it, just in case.