EMG Colt Licensed Stripped M4 "Builders" AEG Rifle (Color: Black / 400FPS)

"Follow up to last review: important to note that mine did not have a front gas block as pictured, but rather a front triangle sight with front mounting ring for a handguard or RAS. Important difference depending on your build intentions.

"For those of you looking for components for ground-up, high quality M4 builds, here's a more detailed review. This is indeed OEM by King Arms, but don't let that scare you off. This is the nicest full metal King Arms Colt trades receiver I've come across. Smooth, thick casting, well formed. Good realistic looking cast-in Colt trades and (I believe) unique serial number, not laser etched and too sharp looking like VFC's. Nice authentic (smooth and slightly thick) black finish. Accessory parts (selector, forward assist, mag release, dust cover, etc) are a nice phosphate gray finish. Both upper and lower are well formed and to exact Tokyo Marui spec, so it won't fight you with parts or gearbox/ hop-up. My Maxx Hop slid right in without any issues. Dust cover opens with pull of charging handle, and fake bolt stays back to access hop until released by bolt release. Typical King Arms, and it works. Pistol grip is a decent polymer molding and should suffice for most builds. Gearbox and internals are standard KA; not the best, but not the worst. I won't comment on function since I'm re-building the internals without ever trying the stock gearbox, but since it's to a proper TM spec changing out the gearbox won't be a problem and I'm putting in a Retro Arms. Barrel is aluminum with a jet black finish, and uses a questionable 2 part delta ring attachment ring to thread onto the upper receiver, rather than the standard threaded delta ring that requires an armorers wrench to install but is simpler and stronger. This is a weak point that the demanding builder will want to replace. Triangle front sight is attached with flora pins and one hex screw hiding under the front sling mount. Overall sturdy. Buffer tube has a separate, gray finished castle nut, a nice touch, and the rear of the lower receiver is formed to accept standard AEG type sling plates. A ZCI Sopmod stock slid on nicely with almost no wobble. Receiver take down pins have retainers so they don't fall out and vanish, and have a solid fit to keep the upper and lower solidly together. Have not tried multiple mags in the magwell yet, but thus far my MAG Brand 190 Metal Midcaps -my absolute favorite- fit perfectly. This bodes well for magazine fit. I'm hard to please, but this receiver put a big smile on my face when I opened the box, and a bigger smile as I've worked on this build. I'll probably buy a second one just to keep on hand before they become unavailable.

"The beautiful thing about this kit is that it is what you make of it. I got it on sale for $250 and have no regrets. I have several high end Airsoft guns of all sorts of brands and platforms and this by far is my best gun. I’ve titan gated it, threw a new motor in it, got a Prometheus barrel, bucking and hopup, got a 12 inch Daniel defense rail and it’s absolutely insane. It looks great and easily has the best performance of any Airsoft gun I’ve ever owned. It has pinpoint accuracy and can reach out and touch people. The beauty of this product is your not paying for all the parts of a gun your going to replace. Your just picking out the things you want and you know will preform. I highly recommend this to anyone that wants a high performance gun looking the way you want it to look.

"Received and finished building out this "kit" with a fixed triangle front sight, RIS handguard and 7.4 lipo battery that fits in the buffer tube. I am really impressed with the kit and happy with its performance. I don't have a chrono, but it seems to be hitting hard. The functioning bolt release is a cool touch and I love the Colt markings. I didnt take apart too much, but I saw that it has a king arms CNC high torque motor and working "quick release" spring guide. Very cool "build kit" and worth the money when it goes on sale for $199!

"Good gun but should have waited at least another week for the deal and saved 80 pulse dollars :/

"Fantastic gun! I would buy this every day of the week. Its super nice. The fps is very consistent, and the rof is actually pretty awesome, its somewhere between 20-30 rps, which is great out of the box.

Pros-
Either 350 or 400 fps with little variation in shot to shot
High ROF
Very durable
Everything is stiff and solid
Quick change spring

Cons-
A average hop up
Metal scratches easily
Everything is stiff so initial takedowns, and such actions are overly difficult

All in all i would say its a 9/10 out of the box, and once I put all my stuff on it, and wore it in a little its very easily a 10/10 gun.

"I bought this gun during Black Friday last year. Personally I love customizing my gun, and this Builders M4 is a dream come true!

Pros:
- It's an open canvas; you can add mostly any aftermarket parts for M4's/M16's
- Lightweight, even with all metal parts (the only plastic is the orange flash hider and the pistol grip)
- Accurate and great FPS
- The functional bolt stop really works, allowing for easy hop-up adjustment
- Has its own unique serial number engraved into the lower receiver with Colt logo
- Wired to rear with Deans connection in the buffer tube, allowing for a lot of options for stocks and handguards.

Cons:
- The paint chips a bit on the buffer tube (but you can just replace this)
- I wish it came in Tan, but I can live with this
- It doesn't shoot lightning bolts

Honestly one of the best airsoft guns I ever bought. If you like tinkering around with external parts and making the gun your own, this is the one for you!

"Only get this when it is on sale, because $200+ for a base body is not worth when me and others experience a brand new product having internals that are faulty in some major way. But when it is on sale it is worth it if you want a Milspec base gun that has internals and a body that with a little work can become a very good rifle. Got mine tidied up by a local shop with the gearbox worked on and the hop up unit replaced with a emg unit. In the end it is a good body but if your expecting a fully functional high quality base gun that you can just slap on some furniture this isn't the one.

"I picked this up after seeing it in the Epic Deals section every now and then. While not directly indicated in the description, there were rumors that this contained SHS internals. No other details other than speculation from people who don't have one, and looking for a youtube video was out of the questions since no one ever tears down a gearbox in them.

Here are the internals after completely disassembling it:
Gearbox Shell - King Arms 8mm QC.
Gears - 18:1 set like SHS but with King Arms etched into them. A standard plastic sector delayer was included.
Bearings - 8mm from some Chinese company. Not great but not bad.
Piston - SHS pattern but red. Has 1 tooth removed for AoE. It is FMR.
Piston Head - Polymer with just a single washer holding it onto the piston body. No brass retainer.
Cylinder Head - Polymer with Brass shaft and flat pad.
Cylinder - Brass type 2.
Nozzle - 21.1mm, no O-ring.
MOSFET - Inline LR7843.
Motor - Chaihai 19TPA Neodymium with D pinion.

The first thing I did when tearing it down was to remove the factory lube, Radius cut the cylinder window, widen wire channel behind the trigger, and remove wire channel pegs. I also discovered that the piston rack was not adhered to the body and the piston head was pretty loose. AoE was terrible, so I added an Air-pad to the cylinder head. I replaced the nozzle with a Lonex O-Ringed nozzle. Checking the shimming, I needed to adjust the depth of the motor just slightly while locking in the adjuster with a small dab of super glue. The Spur gear also needed .2mm shifted to the top, while an additional .05mm removed from the bottom. The sector gear needed .1mm removed from the top. The gearbox was not screwed in tightly, so those adjustments to the shimming were very much needed. I also ended up replacing the MOSFET for a TITAN advanced, which is why I widened the wiring channel behind the trigger.

As for the stock hopup and barrel, I immediately swapped it out for a old school Dees 6.01mm/363mm TBB with an rhop patch and a flat hopped prowin unit

Externally, I added a one of the new style CYMA stocks you find on the QBS line. A little duct tape on the buffer tube eliminates all wobble. The rail I installed was a Madbull DD 12.5" RIS II. The rail was not super flush with the receivers top rail, but it's not too big of a deal. Sights were some cheap Knights Armament flip up sights.

At the price I got it, it was still a great deal. The receiver is nice and not too much work was needed to get this up to top shape.

"All around good build quality and gearbox is nice. But if you plan on throwin a rail on and playin, don’t. The hopup and barrel are super inconsistent and can’t hop .28s. If you put too much hop, you’ll start double feeding and jamming. A little disappointed given its EMG, but i got it for a good deal.