Arcturus ARM Series URGI MK16 M4 Airsoft AEG Rifle
(Model: 11.5" / FDE)

"My last review was never posted, and since this gun has no reviews here as of this writing, I'll try again.

Pros

Externally, it's absolutely amazing to look at and feels durable for casual airsoft games or milsim events
The orange cap on the flash hider is easy to remove and put back on (all you need to do is remove the flash hider and the cap should come off), making it very convenient to travel with and comply with travel laws within the country
Pulling back the charging handle, the mock bolt opens and locks to reveal your hop-up unit, and it's easy to adjust it when you need to

Internally, the gearbox is a V2 proprietary gearbox, but it does come with upgraded parts, and out of the box it sounds great for out-of-the-box.

- CNC Steel Machined 13:1 Gearset
- Steel barrel
- CNC POM Air Nozzle w/ O-ring
- Ball bearing spring guide
- Arcturus M100 Spring (That's my guess comparing the strength of the spring to a Matrix M100 spring)
- Descent 24k brushed motor
- Despite the microswitch, it has a potted MOSFET, so you could run an 11.1v lipo if you want
- As for the factory shim job, it was actually pretty good, with at least roughly 0.1- 0.2 mm of vertical play in gears

Cons

Externally, there really isn't much to pick on; the only problem I had with it is how stiff the stock was because adjusting the crane stock was quite hard, but that can be solved with a little bit of oil or lubricant

Internally, as I've mentioned, it's a proprietary V2 gearbox, so any other gearbox shell will not fit without grinding in the lower receiver...

- Moving on from the upgraded parts, the bucking, bearings, cylinder, cylinder head, tappet plate & tappet spring are all generic factory parts you'd find in any brand new gun
- Disassembling and assembling is more complicated, being proprietary
- If you buy this version, you will not be able to switch it to a brushless motor due to the microswitch only being compatible with brushed motors
- Another problem is that a standard V2 MOSFET will not fit in the hybrid gearbox shell without grinding (the Arcturus ETU will likely only fit this if you want to switch to brushless in the future)

In conclusion, I'd say this is great for the price. Despite the gearbox being proprietary, it functions great out of the box, so you can definitely play games or partake in milsim events without upgrading or tinkering with it, but in the long run you might want to consider upgrading the factory parts I've listed. The weight and balance feel nice without attachments, so your arms won't get fatigued as much in long games. As for a recommendation, I only recommend this gun to experienced airsofters and milsim players already long invested in the hobby due to the price being exorbitant for new players or parents looking to buy their kid their first airsoft gun (unless you're someone who has deep pockets, then go for it).

"To start, to get what you paid for is quite nice; you get performance parts such as a nozzle with an O-ring inside, along with a premium 13:1 gearset, steel tightbore barrel, and a good stock hop-up unit. So I'll get straight to the pros and cons of this particular rifle.

Pros:

Has good performance parts out of the box, so it can help you save money on buying performance parts
You can switch out some parts with compatible V2 gearbox parts such as the cylinder or piston
Has high potential to be better if you're willing to put in the effort and time (And money)
Great trigger response when I used a 7.4 lipo battery, so I can't imagine how much better it will be with an 11.1-volt lipo battery
The externals are beautiful and durable
Not too heavy at all since parts of the body are high-quality plastic
The orange cap on the barrel is easily removable, and I can always place it back again if needed, making it very convenient
Additional conveniences are tools you might need, such as Allen wrenches and a tool for the stock nut
Overall, a good value gun to invest in

Cons:

The gearbox shell is proprietary, so parts such as the microswitch cannot be switched out with a standard V2 ETU
The gearbox requires a lot of patience to work on since it's not a standard V2 gearbox
Lack of battery space (I strongly suggest you buy a stock with a battery compartment if needed)
I found the factory screws were way too tight on the gun, and I ended up stripping one inside the grip

Overall, this is a good gun for the price if you're willing to put up with a proprietary V2 gearbox. It's not a gun I'd recommend for beginners, but for avid or expert airsofters in the community (Which is the main point of it anyway).