What would i need to build a GBB M4?

[WELSH_DRAGON_AIRSOFT]

Currently have 2 GBB M4s, WE and an LM4, anyway i want to get rid of my WE and with the money i will do what ive wanted to do for years whcih is to build my own completely custom M4/AR.
So with my general Knowledge of my M4's, i can only think of the main components to build one. Heres a list of what i think ill need, please tell me if ive missed anything....
.Upper+Lower (Think ill go with the WE Colt trademarked ones as they are nicely built)
.Barrel + Nut + F Hider.
.Choice of Rail.
.Bolt carrier and nozzle or NPAS. (Can buy ready built)
.Charging handle.
.Buffer tube + Buffer and spring.
.Trigger box (Buy ready built and assembled)
.Bolt catch
.Mag catch (can buy pack that comes with all springs and pins)
.Grip
.Stock
And then i believe that is it??? Mapping all the internals in my head i cant think if there is anything else you would need? Because it is simple if that is all you need, just need to buy the packs which have all the parts for a specific component and whack them all together?
Please let me know or if you have any tips n tricks ill be bery grateful!
Cheers!

[Ells]

Re: What would i need to build a GBB M4?

might want a hop chamber, and inner barrel a (the main) problem (excluding costs of not deciding to use a donor gun instead) that you will probably run into is the different tolerances of using lots of different manufacturers which may interfere with your build.

[WELSH_DRAGON_AIRSOFT]

Re: What would i need to build a GBB M4?

Haha yeah forgot that one So your saying avoid cheapy internals and find parts that are compatable with eachother? I know WE hammers arent great, but ive just looked at the RA tech Trigger box and how can you justify paying £125 for a damn trigger box haha! Thats amlost half of a New WE!
Thanks

[Heinz]

Re: What would i need to build a GBB M4?

Frankly, you've missed loads. Complete ejection port assembly and complete forward assist assembly. Plus trigger guard and pin, buffer detent spring assembly, receiver pins, detents and springs. Grip screw, trigger box screw, trigger box pin.

The issue you're going to run into isn't the availability of big parts - it's getting hold of the little parts that's going to cause you problems. The bolt catch spring for example, or the bolt catch, forward assist and trigger guard pins. That kind of stuff. And WE being WE, they ain't normal roll pins - they're WE specific pins with a knurled section on one end. Then you have the problem of cost. I absolutely guarantee that you'll spend more building it from the ground up than you would buying a full gun, flogging the parts you don't want and keeping the ones you do.

**edit**

Don't bother with RA-Tech, their stuff is cack. Overpriced cack. And the same goes for most of the New Age stuff i've had my hands on as well.

[WELSH_DRAGON_AIRSOFT]

Re: What would i need to build a GBB M4?

Thanks Heinz but i did mention that all the Major parts id be buying id buy them in a ready made pack with all the springs and pins. I wouldnt have to get hold of all the little parts because they come wih eachother!
I didnt forget the F Assist and the Dust cover, they all come wih the receiver pack. Every body pin and spring comes with the receiver pack, i do know every pin and spring in the book haha. Again the pins that hold every internal component to the reciever comes within the pack, and everything that binds the internals together is already with the individual components . Otherwise yes it would be a pain to get hold of everything. Cheers

[Heinz]

Re: What would i need to build a GBB M4?

You have a PM....

I know for a fact that WE do not sell parts packaged like that. They never have done.

[PureSilver]

Re: What would i need to build a GBB M4?

Having researched this extensively for a variety of GBB pistols and rifles, Heinz absolutely nails it:

I absolutely guarantee that you'll spend more building it from the ground up than you would buying a full gun, flogging the parts you don't want and keeping the ones you do.

Again, I have literally tried to do this with Hi-Capas, which have by far the best aftermarket support of any gas-powered airsoft gun, as well as being much, much less complex than a full-scale select-fire GBBR. It is categorically impossible to buy all the parts of even a Hi-Capa on the aftermarket - you simply cannot buy the odd few springs and tiny parts without a donor gun. If you can't do it with a Hi-Capa - which is the most customisable gun in airsoft and has been around for eons - you certainly can't do it with a GBBR with twice the parts count and half the service life. Even if it were possible, Ells makes an excellent point:

a (the main) problem [...] that you will probably run into is the different tolerances of using lots of different manufacturers which may interfere with your build.

None of these parts f***ing fit together. A friend recently purchased - at great expense - an RA-Tech receiver set for his GHK M4. The bolt carrier literally does not fit in the upper receiver; tens of hours of sanding at a minimum will be required just to get it together, never mind shooting. The less of your gun that comes preassembled from the factory, the more work you will have to do to get it working and the higher the chance it will never work satisfactorily.

Getting a GBBR running properly is a mission in and of itself, never mind building one out of parts that were never designed to go together first. Pick a gun that you like - I'd recommend a GHK if you can stand the trades, and a ViperTech or Inokatsu if you can't and aren't afraid of troubleshooting - and customise it.

[Heinz]

Re: What would i need to build a GBB M4?

You won't go wrong starting with a GHK. Recent VT's are pretty sweet as well. Inoks, however, are money pits (straight out of the box) if they weren't VT OEM'd ones (i.e. going back a few years). They make good looking wallhangers though.