Best Full Metal GBB M4 ?

[Pre-1898]

Can anyone tell ma what make is the best, most realistic FULL METAL Gas blowback (co2) M4 rifle. I am looking for something comparable (quality wise) to the real M4 and if possible bearing trademarks.

So many brand and models out there but I know very little about them.

[Reckless]

I think Co2 narrows your search down right away... WE I think...

[George Burdell]

IIRC the inokatsu m4 has CO2 mags coming out, and it appears to have the best external quality of all GBBRs, but it costs some outrageous price.

[Pre-1898]

I would probably consider Greengas and propane as well but propane stinks as hell !

[anadon]

I like my KJW M4. However, the mags cost a lot more than the AEG mags.

[kullwarrior]

This has been shot at so many times

Already, make it system choose a system.

KJW -OOTB most reliable, Thermold magazine, NO CO2

WE Open Chamber -Essentially like except STANAG magazine, Nozzle are prone to break when double/triple feed

WE AWSS -Fewest moving part (less part breakage), long term requires trigger set upgrade. Hopup is kinda finicky

Magna System -Has the most aftermarket parts. Long term the most expensive

[George Burdell]

Why exactly do people want co2?

[Tex]

+ less cool down, more kick, less stink, better in winter.
- harder on internals, less stink, more money both in repairs and in gas , maybe more.