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G&P Full Metal M4 WOC GBB Airsoft Gas Blowback Rifle Challenge Kit (Model: Blank Receiver)

34 Customer Reviews

by Stephen L. on 01/08/2018
"I will start by saying this is my first gas airsoft rifle. I have a couple gbb pistols but had no rifles. I had no previous knowledge of the inner workings- but, now I do. I was hesitant to buy this kit because of reading negative reviews. However, I really wanted a gbbr but couldn't give my wife a reasonable explanation that made spending $400+ okay. I will end up with that spent, but it's easier to do $20 at a time.
The kit was nicely packaged with all pieces of a particular part grouped together- trigger, hammer, bolt catch etc. I wasn't missing any pieces nor did I have any leftover. The instruction booklet was very helpful, even though there were no written directions. They provided me with an order to the assembly and names of the parts I was assembling. I did go to the internet a couple times and was able to find what I needed. Thanks to having the proper names from the booklet.
I believe the makers of the kit have been reading and listening to the reviews. I was pleased with quality, still not steel, but zero plastic( other than the nozzle). Everything was neatly packaged and I had everything needed except a mag. and wasn't supposed to have one.
In my opinion, this kit is awesome. With a good bit of patience, a file and some sandpaper, you can come out on the other end with a very nice gbbr. Well worth my money and time.
by Jacy L. on 12/21/2017
"Great kit, I'm very happy with it.

One thing for folks to know is that G&P has been improving this kit over time. I bought a bunch of parts preemptively that I don't need because the kit already has them (or better parts).

The Navy Seal kit comes with:
- a different nozzle unit - it appears to be the upgraded unit
- the hammer is steel AND has roller. The roller is a very nice one, it's wide - much wider than the roller on the king arm or matrix hammer upgrades. I bought the matrix roller hammer upgrade assuming this kit did not have one, and it's clearly inferior to the one that comes in the kit.
- the trigger lock is steel and has bushings to stabilize it (better than the upgraded units out there)

Bad things still in the kit:
- The buffer lock is not steel, though unless you are upgrading the recoil spring, weight, and travel, I don't see why you need a steel one.
- Bolt catch is not steel
- Trigger is not steel
by andrew z. on 02/15/2017
"On first inspection this kit seemed complete but after I started to assemble this kit I realized that the recoil spring was missing. Easy fix once I called evike, they said they will try to locate it and if they did they can send it out to me, or if they can't find it within 2 days they will accept a return on my kit. I asked if they would just be able to send a replacement spring if they couldn't find the original due to the fact that the kit is mostly together already and the gentleman on the line said that that can be done also. Great customer support, within 15 minutes everything was sorted out.

Some of the internal parts of the kit seem low quality but I was aware of this going into the kit. This gun is a great gun if you want a project, as the assembly is not the easiest, but can be done with the manual and some effort. This is not a kit you will have done in a couple hours though, it's really is a challenge.

You will not need any experience building guns to buy this kit!!!!! Follow the instructions and you will be okay.

The amount of aftermarket and replacement parts for this gun is emense and I do not see myself getting bored of upgrading and changing the gun. I plan of getting more then one upper going at a time so I can have a very dynamic setup depending on the course/game.

The paint on the reciever of the gun is impeccable and I love the finish. G&P has done a great job detailing every part on the exterior of this kit and I am very impressed with the looks so far. If there is one thing I recommend getting with this kit other then the magazine (which is not included) is a rear sight, as the stock one is very poor in my opinion.

Overall- very impressed and happy with this kit and my first purchase on evike! Evike has been very helpful with finding the missing part and no other company has had customer support this good. 8/8 was gr8 m8
by Robert v. on 09/28/2016
"This is a amazing gbbr if you have tech skill to assemble this rifle its great and if you upgrade the internals to steel and fine tune its a beast i love it and recommend buying it with the exception that the buyers have patience and knowledge of assembling small parts and springs instructions are easy to follow if you can follow a plastic model car or similar instructions you can build this you will need to do some file sanding etc tuning is highly recommended if done right you will love it!!!
by Katelyn H. on 09/22/2016
"This is really a awesome replica, after installing a npas in the bolt and fielding it at my local cqb arena I am pretty happy with it. Honestly the magpul mags are the better option as stated in other parts of this site and on the net. The fill valve in the stanag style magazine are the TM style valves that allow gas to spill out as your filling it so they cannot over fill, this is awesome when you have a japanese airsoft gun like a tm or a wa. Here though the system is a little lack luster and causes leaks, that is a different issue seeing as this is the kit and no magazine is included so I digress, Once I got done scratching my head and swearing at the instructions for telling me to put the full auto sear in after the fire selector (watch johnjayrambo on youtube he has a video on how to build a lower receiver) the kit went together very quickly and easily. Basically if you can lace your boots and consider yourself semi competent this is going to be pretty straight forward stuff here folks. As soon as I was finished assembling the whole thing I loaded a magazine and let it sit for about 5 minutes, then I slapped it in the carbine with a satisfying clickity clack noise that is very reminiscent of handling an actual firearm. The first time I shot it I was extremely pleased that it actually worked, not only did it work it is the coolest airsoft gun I've ever seen or used. G&P's WOC is so much fun to shoot and handle, it is extremely finicky though so expect some experimenting and fine tuning. Definitely not a platform for just anyone though, but once you put it together and get a couple of suckers out with it you will feel like a Jedi master.
by Ryan C. on 04/24/2016
"This thing was quite an experience to build. The little Allen screw that's used to tighten down the front sight stripped due to the fact that the material is so thin. It was an easy fix though, just used a beefier Allen screw to replace it. And also just a heads up, my receiver has the skull frog logo but does not have the punisher skull or navy trademarks so just beware of that. After it was finished, this thing is a beast. It has a nice weight to it and it hits hard. I had no experience at all with gbbrs and it wasn't as difficult as I had thought it would be. So if you're hesitant to buy this because you're not sure you'll be able to build it, just buy it. It just takes a little tinkering and mechanical knowledge to get it together. There's also a million different ways you can customized me upgrade this with after market parts. Overall, a great buy, well worth the money in my opinion
by Matthew H. on 03/10/2016
"Fun to build, came with all the parts, though I'm currently waiting on an NPAS unit before finishing the assembly. Well built. Excellent finish. Be careful about the trigger guard install, in my infinite wisdom I tried forcing the retaining screw for the fromt half of it through with the outside of a leatherman multi tool. The end result was I am now missing a large chunk of skin on my knuckle just above my right thumb. Point is be careful. The kit was incredibly easy to assemble, the instructions are like that of a Lego kit. Just get some snap ring pliers, a nail, mallet, pliers, allen keys, a metal file, and a ton of lube, ignore the cashiers strange looks at your local Wal Mart and you're good to go, all set to get into a hot sweaty, back aching, hand stinging, wrestling match with the auto sear and delta ring, parting the lips of your magazine, and filing down the loading nozzle till it all lies flatter and smoother than 9 month old Coke. Overall. It was fun.
by Rodrigo L. on 11/06/2013
"I just received this kit today and finished within 4 hours of work.

Building this awesome kit was very entertaining and very educational, since i work as an airsoft technician and this helps me understand how m4 gbb work.

Dont expect this kit to work smooth when you finish asembling it, it needs some sanding and LOTS of oil to help the gun wear itself to make it run like it should... remember this is a challenge kit, its supposed that you make some effort putting this together as it should, once it starts running smootly well.. i just gotta say i fell in love with this thing.

Mag efficiency is awesome, holding enough gas for about 80 rounds.. mags take 39 bbs each.

Things to get as MUST, are Hammer with bearing, Sear, Buffer Lock, Bolt catch , all of them made from steel, since the ones that come with the kit wear down easily because they are made from aluminum.

I havent field tested it but overall i would definetively recommend this.. Man id even buy another one just for the fun and challenge of building it!
by andrew b. on 03/13/2013
"I have recently purchased this kit and it is very awesome, after 2000 rounds the only thing to break is the buffer lock, and a steel replacement is only $10 so I can not complain to much. If your are wary of getting this gun because you have to build it DON'T BE!!!! It is extremely easy to put together and I have a very en depth step to step procedure of how to put it together

Easy to assemble.
Two nozzles, one for 300fps and another for 350fps.
Solid construction.
Upper and lower receivers may be wobbly against each other, however it varies, in one of my kits the upper and lower meet very tightly and then my other kit has a pretty sloppy fit.
G&P Pmags will need modified to work in the gun, either modify the gun or the mag catch, again this video can be found on my you-tube channel if you want to know how to fix this.
Great looking gun and after you get the mag or mag catch modified it works like a charm! I have nothing but absolutely great things to say about these kits. If you are on the fence about getting one of these kits do it! They are only a fraction of the cost of a assembled one, plus if you put your gun together to start with you will better understand the weapon, and be better able to fix and maintain it in the future.
by Chris P. on 01/30/2013
"I got this gun a few days ago and its awesome. It took me about 2.5/3 hours to put it together ( I accidently messed up putting the outer barrel on and I couldnt get it off.) Anyway: I didnt recieve a pin to put the auto hammer lock in, the buffer lock broke immedately and the mag has problems. As far as the provided pmag, the bolt gets caught on the black rubber valve on the magazine. Despite those things its a great gun and im sure its fun to shoot (didnt shoot it yet). Also, if your worried about some assembly or any peices they were different than in the picture and in the videos we all watched on youtube: The bolt was COMPLEATELY assembled *woot woot* no need to assemble the nozzle, the buffer is wayy different, rather than a speed buffer or silver solid one, its a black one with a hole in the middle. Lastly, the hard hop up bucking everyone complains about is rubber, super super soft rubber.

Easy to put together
Magpuled out
comes with a magazine
full metal
new pieces

No auto hammer lock pin
buffer lock broke (upgrade to steal immedately)
magazine valve needs a replacement
by Marko S. on 12/04/2012
GBB rifle
Solidly made and very realistic
Based on WA system
Get to learn every detail about your gun buy making it

Came with missing parts
Lower receiver was not in spec
Mags are expensive

Overall, if you love GBB this gun is the way to go just be ready to do some waiting with missing parts.
by Tim B. on 10/31/2012
"the quality of this kit is great for the price!!! that being said i do have a few small complaints. first of my kit came missing numerous parts, i contacted evike about this and they were very quick to supply me with these missing parts after i set a few emails detailing exactly what i needed(thanks for all your help support team!). of the parts that did come in the first shipment of this kit, the hopup unit had a piece completely broken off, again evikes great support team helped me out by having g&p directly send me an entire new hopup unit(not just the broken part) which was awesome. the last downside i have to this is the part of the lower receiver that the trigger guard attaches to near the pistol grip is very weak. on the first hit to get the triger guard pin through it snapped clean off. i read in a prior review that it had happened to someone else and was easily fixed with some jb wield, so thats what im going to try as well. i would not hesitate to buy another one of these kits or to recommend to a friend or anyone else. i test fired it yesterday and it shoot and preforms perfectly. if you are looking for a cheap way to get into gbbr rifles this is 100% your best choice, imo.
by Matthew D. on 10/17/2012
"i love this gun. it took me about 2 hours to build and everything went together perfectly. mine came with an oversized bolt and after about 2 months evike finally got me a new one. mine shot over 425 fps with .25g bbs right out of the box and that was awesome. it is super accurate, im hitting targets upto 200 feet away. it works great and is really gas efficient. if you want to get this then you really need to. i cant say enough how great it is. the cool part is that this comes with a magazine. and its the G&P PMAG, which is actually full metal, but im not upset. its 10x better than the LM4 mags. its super easy to put together, and worth every penny.

shoots 425 fps with .25g bbs
full metal parts
realistic to a real gun
operates flawlessly
is just awesome

it shoots 425 fps with a .25g bb

thats not a bad con but for those that want this for cqb try using heavier bbs or get an NPAS kit for the gun.
by Brian L. on 09/20/2012
"Very cheap for high quality GBB rifle

high quality

mine came with missing parts. i sent evike a mail and am waiting for respond.
doesn't come w/ mag
have to assemble it obviously

Overall, very nice G&P! I wish that some of the parts were not missing so that i can actually finish the gun.
by brett s. on 09/19/2012
"Highly reccomend. Very sturdy externals, ok sturdy internals. Will probably have to shell out ~200-250$ to get internals to mid/skirmishable spec. otehrwise stock are fine for plinking and light battles.

great externals
ok internals
mags only hold 30-50 rounds (do not buy king arms mags, best is G&P then magpul. For about alot 70+$ you can get some prowins)
mags only old 30-50 rounds (lol)
expensive to maintain and mags are expensive

Mine came with a missing buffer tube ring, rear stock mount thing, and barrel nut. I called evike, and they're shipping me them. So don't really worry about it missing any parts.