Help: GBBR 'ground up' build

[rockafella]

I am calling upon the skills and expertise of those of you who own (or have owned) skirmish worthy Gas Blowback AR15's.

I just recently got a great deal on a AGM GBB M4 (yes I am aware of the quality of this gun) but being new to the whole GBBR scene, I was not sure if this would be something practical for my use.
After playing around with it, I have found a feeling almost akin to my first bra strap fumblings in the back of my brother's civic.

So what I am looking for is some advice (please no flaming) and anything that you think I should know about building a gamable GBBR.

I love the realism of the GBBR so anything I can do to enhance that would definitely be something I'd want to pursue. At the same time I want a gun that is durable and can take a beating. I don't intend on debut-ing this baby until the summer games so I have time, I know this is ain't gonna be cheap, but I am convinced it'll be worth it!!

My to do list-(not in any particular order)

Upgrade the OEM body- I love the PRIME MK18mod0 body, but $1,200 is a bit too steep at this point. Basically I want to build an MK18 CQBR, so a good solid one with those markings is what i am looking for. Some minor details that I would also like to fix if possible.

-I don't like the way the buffer detent looks in the AGM, I want one that looks like the ones on the Inokatsu and WE ones.

- The forward assist does'nt seems to actually be funtional like the one on the Inokatsu and WE ones. - Mind you I have not yet actually inspected this area - could just not be lined up properly.

-The charging handle; you know how on the real steel ones, you have to insert it at a bit of an angle initially then put the bolt carrier in, are their any AS ones that will have the same thing? Is there a charging handle that has a hole at the front for the gas tube?

-The RIS, and the barrel nut assembly were very wobbly and the markings were not very real looking (and cheaply made) - so I have remedied this problem by replacing all those including the gas tube. (there was also a wobble between the upper and lower receiver)

The Bolt Carrier - I want one of the heavy duty steel ones that will give the most recoil feel. Also looking for one where the gas tube part is actually hollow. Also, those two holes on a real bolt carrier that are just slight depressions on the AS versions, is there one where these are actual holes?

The bolt - that plastic one has to go!!! I am looking for the most realistic looking one that is also really tough. Also, I want one that is the dame dim gray color as the bolt carrier. Anyone have any recommendations?

The Buffer and spring - already replaced the cheap plastic buffer with the aluminum one and the spring with the professional one from Airsoft Surgeon.

The Hammer - I need a strong one that will stand up to some abuse with redgas (anyone know if the use HPA is possible? - to eliminate the cool down factor)

The Bolt catch - it is very wobbly and does not always grab, and sometimes it just takes a little jolt of the gun for it to release. I read that it is recommended to get the 'soft' catch when upgrading the bolt carrier.

Hop- up- The plastic OEM one needs to be replaced! Looking for a good aluminum/rubber one. Suggestions?

The fire selector switch and retaining pins - they just don't feel tight, there seems to be alot of play, not sure if i need to replace those but deffinatly looking forward to Huangs steel upgrades.


OK, guys that is my "to-do" list so far, If you think there is something i need to add to that list or any particular recommendations as to what parts I should get and the compatibility that would be greatly appreciated. And if I wrote somethings here that you think is asenighn - be gentle, this is my first experience with the GBBR's and yes i have read all the reviews on parts/upgrades that members on ASC have posted.

Thank you in advance. And if you have this stuff for sale let me know.

***DON'T TELL THE WIFEY*** LOL
My grocery list (updated as more information is gathered) -in order of priority (and budget)

RAG-WA-bolt (loading nozzle)-015 - New Version N.P.A.S complete bolt-Dimgray - $291.14

Hop-Up & Inner Barrel
RAG-WA-front sight-003, S type - Complete hop up & innerbarrel set - $131.01

Outer Barrel
GP-ACC-WP21 - G&P WA M4 CQB/R Steel Outer Barrel (CQB/R length, one-piece construction, 14mm+ thread) - $96.39

Hammer:
RAG-WA-trigger set-004 - RA TECH WA Steel hammer - $78.38

Metal body w/ trades (not sure on a particular one yet)

[m102404]

Ronan started a whole thread on the AGM model already. He said he was buying up tons of parts and was going to put all the info up there.

Maybe it'd be best to dump this info/questions/etc...there as a post?

(I'm not really, really familiar with this model...but you may need a different stock tube as well...I had heard that the threading of the AGM model was not compatible with other types).

[ILLusion]

1. There are currently no other "MK18 MOD0" marked receivers on the market besides the Prime one. Your only other option is to pick up a blank marked receiver, cut the markings yourself and re-oxidize the finish if you want it done right... but the time and effort put in to that on top of the cost of a cheaper receiver won't save you too much from getting a more premium product such as the Prime.
   
2. If you get the Prime internal component kit to go with the receiver, it will come with the buffer detent you're looking for.
   
3. Your information is incorrect: The forward assist does not work on any Magna based M4 (Western Arms, Inokatsu, G&P, Prime, AGM, etc.)
   
4. The Prime receiver comes with a charging handle that installs just like the real thing - through detents that keep the charging handle riding along rails, even without a bolt carrier inserted. The Prime and Inokatsu charging handles do not have holes at the front. I don't think the G&P ones do either. I'm not aware of any that do.
   
5. Inokatsu has the heaviest bolt carrier, but it can not be used in your oem upper receiver. The next heaviest is RA-Tech.
   
6. If you want heavier blowback feel, also consider one of the heavy weight buffers.
   
7. Heavier blowback generally requires heavy components that move, which will also mean slower cycling times. There is a balance that you must consider.
   
8. The gas tube part of the RA-Tech bolt is actually hollow.
   
9. The AGM bolt carrier design is unique - there are no aftermarket bolts that you can install in to the AGM bolt carrier. You must do a complete swap if you want to get away from the garbage AGM bolt.
   
10. If you're looking for a dark coloured bolt, the RA-Tech bolts are black / Dark grey (depends if you get the aluminum or plastic one.)
    
11. Like I suggested to you before, Prime or RA-Tech. Both steel, both with ball bearings. The RA-Tech one has more ball bearings. I believe G&P has a steel one as well, but I haven't handled it yet.
    
12. Like I recommended before to you via PM, the RA-Tech bolt catch is a good replacement, especially if upgrading to an RA-Tech complete bolt set.
    
13. Hop-Up: Prime has a WA copy, as well as a conversion hop up that allows you to use standard AEG barrels & hop up rubbers. Many users claim the RA-Tech setup to be the most superior to date.
    
14. Many aftermarket switch assemblies are on the market.

[kullwarrior]

EVERYONE BACK OFF THIS ONE IS MINE!! (lol joking)

k I've build one before already, some where near your demand.
This build is basically if you want go full out and your budget limit is approx. $2-2.5k
All in USD unless otherwise stated

*Bolt Carrier: RA-Tech Steel Bolt Carrier or Prime RA-Tech is probably more durable since it doesn't have hollow end like on the prime
*Bolt: Gen2 Aluminmium NPAS, Make sure get the Aluminium Nozzle head, and replace the red O-Ring with a smaller one, (Mine was too big, and it got tore apart)
*Trigger Group if you are building of scratch get Prime, as its the only one, otherwise enjoy finding all the lil parts
*RA-Tech Steel CNC Hammer, Prime is a steel one, I don't see anywear so Im not sure if you need it.
*Buffer: Use AR-15 Buffer, the airsoft ones are too weak against prime buffer lock (prime is the same one as ar-15 which will destroy buffer)
*Sprng: either AR-15 recoil spring or RA-Tech Summer type recoil spring (AR-15 is probably for HPA, CO2, and Red Gas)
*Hop up: This is where's interesting, My experience with G&P is been awesome, RA-Tech is pretty much the same.
*Inner Barrel, G&P ones vs PDI & RA-tech, neither are clearly better, PDI has a lil tighter than RA-tech (by about 1") RA-Tech is about 1" tighter than G&P. PDI has problem with bbs jamming. I recommand G&P or RA-Tech.
*Fire selector: at this point this is determine by what model you use, WA spec use G&P, Prime spec obv use Prime. I'm unsure right now whether AR-15 selector would work with prime or not (prime said its same spec as AR-15)

General List w/ est cost:
1X Prime MK18 MBK: $800
1X Prime Lower Receiver Kit $205
1X Prime Barrel Extension: $35 (If you choose G&P Hopup& Inner kit you don't need this)
1X RA-Tech NPAS w/ Gen2 Al Nozzle: $265
1X RA-Tech Al Nozzle Head & Red O-Ring: $10
1X RA-Tech Bolt catch (need fitting): $15
1X RA-tech Inner Barrel and Hopup: $110
1X RA-tech Summer Type Buffer Spring: $10
1X AR-15 Charging Handle: $30-200 (30 being DPMS, 200 being PRI)
1X AR-15 Buffer: ~$20
1X AR-15 Buffer Spring: ~$10
1X G&P Front Set w/ Stock (otherwise you'll have to buy stock) $175 (RAS Short)
1X G&P M4 Pistol Grip: $25

Anymore question feel free to ask me

[RacingManiac]

Forward assist does function if you have the bolt fails to complete return to battery, in that pressing it does physically move the bolt carrier....

Also things to consider, if you want heavier recoil, consider running lightest possible front end assembly, light weight RAS, aluminum outer barrel, and less accessories up front. The "recoil" you feel is the physical force exerted by the moving assembly slams on the back of the buffer tube and the jolt it imparts on the gun. The more mass the gun carries, the less you are likely to "feel".

[rockafella]

Thsnk you for all the info guys, this is exactly what I was looking for.

on the Redwolf Website, they claim that the forward assist actually works on the WA GBBR
http://redwolfairsoft.com/redwolf/ai...l?reviewID=188

[ILLusion]

Ah, maybe it does. I only pushed it when the bolt was properly seated... I assumed it did nothing, but I could be wrong on that.

[bodydropper]

Nice! Everything that I need to know to upgrade my AGM. Cottoni (retailer) hook me up! His service was quick it took less than a week to get to me.

[kullwarrior]

Originally Posted by ILLusion

Ah, maybe it does. I only pushed it when the bolt was properly seated... I assumed it did nothing, but I could be wrong on that.

Oh yes it does I'm guessing at-15 part will work. I think ar-15 forward assist is better since it's cheaper and it will have the pin that holds fa to receiver.

[rockafella]

Do you guys know if drilling holes in these 2 fake holes on the bolt carrier would affect any functionality? Or are there any boltcarriers that have these that actually have a bit deeper holes?


Also, is it possible to get a bolt carrier that doesn't have these rectangular tabs or at least one that is not so apparent? _ I guess changing the bolt/loading nozzle to a dim Grey aluminum one would work.

[Qlong]

Drilling renders the gun useless, the gas allowing the blow back function to work would just escape from there.

[Ronan]

Can't believe i miss this thread LOL!

After a lot of trial and errors and wasting money i found that simply dishing out the $ for a complete ra-tech bolt is the best solution (if you want to game your GBBR). Or wait for Huang to sell the new chinese npas bolt.

Anything made for the WA will fit the AGM with zero modifications. If modifications are needed, theirs good chances they are also needed to fit a WA.

What doesn't fit:
Stock tube won't fit AGM lower.
Certain nozzle won't fit AGM bolt (but will fit JG bolt that in return fits into the AGM).
Stay away from RA-TECH 'adjustable' take down pins. They break AGM/G&P lowers...

[ILLusion]

Originally Posted by rockafella

Do you guys know if drilling holes in these 2 fake holes on the bolt carrier would affect any functionality? Or are there any boltcarriers that have these that actually have a bit deeper holes?

The seal would break and you would lose all blowback functionality.

Originally Posted by rockafella

Also, is it possible to get a bolt carrier that doesn't have these rectangular tabs or at least one that is not so apparent? _ I guess changing the bolt/loading nozzle to a dim Grey aluminum one would work.

The RA-Tech bolt carrier has like-coloured tabs now. The original ones were silver on black.

[rockafella]

Originally Posted by ILLusion

The RA-Tech bolt carrier has like-coloured tabs now. The original ones were silver on black.

Nice!! Definately gotta pick up one of those soon.

[rockafella]

two questions:

Is it possible to use HPA (for more consistent shooting) without damaging the gun? -If so what parts would you guys recommend?

Also could someone post what maintenance is required to keep a GBBR working smoothly and properly for the longest amount of time (or a link to the user's maintenance guide)