Tokyo Marui Next Generation Electric Gun HK416D DEVGRU Review and Simple Customization

This review covers my existing electric airsoft gun, the Tokyo Marui HK416D DEVGRU Custom (which I'll refer to as HK416 from now on), and also reviews the parts I've already customized.

The real firearm uses the Stoner-style DI (Direct Impingement) system of the M4, which HK (Heckler & Koch) modified into a short-stroke piston system. This kind of information is available on Wikipedia and other sources, so I'll omit further details.

Exterior check

First, let's look at the whole thing from both sides.

appearance

This is a side view of the entire structure.

opposite side

It's basically short at 10.5 inches, but it becomes quite long when you attach the included silencer.

Plus, it looks like it might bend if you bump it, which is a little scary.

With a silencer attached, the length is the shortest compared to the stock.Even when shortened, it's 800mm (80cm).

The trekking poles extend to six sections, but I only use up to the first or second section. (I'm 175cm tall.)

Up the racy bar

This is the right side of the receiver. It has an ambidextrous selector switch and the ASGK logo is engraved on it.

This is the other side. The markings are surprisingly well-defined and realistic.

The receiver has a clear "HK" marking on the left side, but unfortunately, there is no marking on the right side.

Well, I don't really care about the engraving, so it doesn't bother me much.

By the way, there's a swing belt adapter attached to the base of the stock pipe. (Super convenient)

Site View

I don't use iron sights, so I'll check the sighting with the old Tokyo Marui Pro Sight mounted.

Red dot sight illuminated

The viewfinder looks like a typical M4-style sight (I prefer the older Marui Pro Sight for dot sights).

Compared to the M4, the top rail is higher due to the gas operation rod, making it quite easy to look through even with a face mask on.

Grip

This is a close-up photo of a tango-type grip.

The grip isn't particularly thin, but its shape makes it easy to hold. (I personally don't like the so-called A2 type.)

By the way, the most important thing about the grip is the front-to-back width.The narrowest part is 41mm,The thickest part is 53mm.The average width is 30mmThat's it. (Measured with calipers)

Weight measurement

We will now measure the weight.

In addition to the main unit, there was a replica PEQ-15, an old Tokyo Marui dot sight, and an included foregrip silencer weighing XNUMXkg (magazine, without battery).3.6kg (excluding magazine and battery)

The catalog states it weighs 3.7kg (including battery and empty magazine), but for some reason mine is lighter.

Lucky me! That said, it's heavy, so it digs into my shoulder, which is a problem for me since I usually use a one-point sling.

Custom

I did a little customization on it a while ago, so I'd like to share it.

Takedown

First, we'll take him down.

Remove the pin in the yellow circle and pull the upper receiver to easily detach it.

The area circled in red contains a spacer to eliminate play between the frame and the gearbox, so it's what's known as an R1 lower frame.

I think I did take it apart once and adjust the shims.

Barrel and chamber area

Remove the barrel and chamber assembly.

Check the degree of the hop's protrusion.

The inner barrelOriginal inner diameter 6.08mm, length 275.5mmからLaylax BC Bright Barrel, 6.05mm inner diameter, 285mm length.I'm changing it to this.

・LAYLAX BC Bright Barrel, Inner Diameter 6.05mm, Length 285mm
I think this barrel offers the best value for money. Also, since it's made of brass (or a copper-based material), it's easy to work with, which is a big help.

I read somewhere (I forget where) that an inner diameter of 6.05mm provides the best accuracy.

Regarding length, it can accommodate a 285mm attachment when extended to the very edge of the flash hider.

I previously calculated the relationship between air volume and barrel capacity, and since the cylinder volume was large, I extended the inner barrel (I will explain the calculation formula later).

The hop-up chamber has a rattle-preventing ring, a chamber rotation-preventing spacer, and a press-fitted brass pipe for airtightness.Tokyo Marui's latest genuine chamberis being changed to.

Although it's an original part, I think it performs quite well in terms of precision and airtightness (it's very well thought out).

・Tokyo Marui Genuine Barrel & Hop-Up Chamber for Next Generation Models
This is the ultimate hop chamber. It's the latest version.

The chamber packing isMiyagawa Rubber's long-handled slim nitrile rubber with hardness 50 and pusher rubber.I've included it.

The ammunition to useSince it weighs 0.2-0.25g, it has a slim hardness of 50.We have set it to.

Thanks to the long-range hop-up, the muzzle velocity doesn't drop too much even when hopping up, which is a great advantage.

・Miyagawa Rubber Long-Handle Slim Nitrile Rubber Hardness 50
For high-cycle or heavy ammunition, the Long-Range Medium with a hardness of 60 is also recommended.

Battery connector change

I don't like the so-called SOPMOD type, so I changed it to the Tamiya mini connector specification.

It will fit a bifurcated LiPo battery like the one in the picture below.

The original SOPMOD type wiring was not very responsive or versatile.OP No1's LiPo connector converterI'm changing it to this.

Batteries like the ones pictured (ET1 1400mAh dual-prong battery, k-hobby 1600mAh dual-prong battery) fit easily.

Thanks to the LiPo battery, semi-lockouts have decreased considerably. LayLax now sells fused versions, so those are better.

・LAYLAX Next Generation SOPMOD Stock Conversion Connector with Fuse
I think this one is better right now.

The battery connectors are mounted together on the right side of the stock.

The balance connectors for the LiPo battery are grouped together on the left side of the stock.

Install the bad plate in the middle, making sure that the wiring does not overlap as much as possible.

There is no fuse, but the Tamiya mini connector has a capacity of 10A, so if there is any abnormality, the connector will burn out, and I'm using that as a fuse (this is not a recommended method).

I wouldn't recommend trying to copy this too much, but it's working fine so far. (LayLax's has a fuse.)

Based on my previous calculations, the EG-1000 motor requires around 4-6A of current, so I've decided that a Tamiya mini connector will suffice.

I also installed an SBD (Small Block Diode) to prevent switch burnout.

Actual firing performance

The shooting conditions were as follows: ammunition was Tokyo Marui 0.2g bio BBs, the battery was an ET1 1400mAh Red Line with a total voltage of 7.6V, and the measuring instrument was the standard XCORTECH X3200 MK3.

With an initial velocity of 97.9 m/s and a cycle rate of 758 rpm, the rate of fire is 12 rounds per second. The initial velocity is a bit too high.

The next generation's out-of-the-box muzzle velocity is around 90-92 m/s, so that's quite an improvement.

I want to increase the cycle rate a bit more.

If you're interested, please also check out my review of the chronograph.

Summary

In summary, it's a great airsoft gun with virtually no drawbacks other than being a little heavy.

With just a few tweaks, the initial velocity can be pushed to its limits, and the rate of fire is only slightly slow, so it's pretty good overall.

In the future, I might incorporate electronic trigger-related features.

My future customization plans are set. I'll be replacing the handguard, adding a slightly higher rate of fire, removing the recoil, and eventually installing an electronic trigger.

・Tokyo Marui Next Generation HK416D DEVGRU
The gimmick and bullet trajectory are the best in the industry. It's a great value as it includes a suppressor, grip, and a swivel for the base of the stock pipe.

・Tokyo Marui Next Generation HK416 Series Spring-Powered 82-Round Magazine
This is the original magazine. It normally holds 82 rounds, but can be switched to a realistic 30-round capacity.

・Tokyo Marui Next Generation HK416 Spring-Powered 520-Round Magazine
This is a genuine high-capacity magazine. It holds 520 rounds, allowing for use as a support weapon.