I’ve long been a fan of the SCAR-H platform, but my experiences with the VFC SCAR-H and its consistent feeding issues, along with the poor build quality of the proprietary hop-up, eventually drove me to finally put down the cash for Tokyo Marui’s version.
The TM SCAR-H lives up to the Tokyo Marui reputation for excellent performance right out of the box; 150 foot shots are easy as pie to make (with a maximum effective range of 150-170 feet), with great consistency from shot to shot. And this is all with 0.25g BBs, and at a paltry 300fps. The recoil of the platform is not as strong as the KWA ERG platform (or even TM’s M4 Recoil Shock series), but is still strong enough to give the gun a pleasant bump against your shoulder with every trigger pull. The bolt release function is always fun to have, and I’ve grown used to bolt lock functions on my other AEGs so I’m used to hitting that paddle.
Anyway, I did have a 407mm 6.03 Prometheus barrel lying around, and I’ve been a fan of the look of the longer 16″ barrel on the SCAR-H that can be achieved via the included barrel extension. Thus I set to work opening the SCAR up to install the Prometheus barrel and perhaps get to the bottom of what makes Tokyo Marui hop-ups so great.
CONCLUSION: Tokyo Marui hop-ups are made of crushed unicorn bones and fairy dust, forged together in the fires of Mount Doom by the dark lord Sauron.
More pics of my (not-so-simple) walk into Mordor after the break.
First things first – getting to the hop up. I followed this guide that was very easy to follow. Thanks, Echigoya!
The TM SCAR-H isn’t your average version 2 M4, where all you need to do is pop the front receiver pin and slide the upper receiver off to get to the hop. No, you need to unscrew eleven screws just to get the upper receiver off, and then you have a further five screws to remove to separate the hop-up from the metal block that it’s housed in. That’s sixteen screws altogether – better make sure you don’t lose any. The takedown also requires the use of a Torx head as well as several hex keys of varying size, so a precision screwdriver/bit set is a must (and really, anyone looking to do any of their own gunsmithing should have a set).
The takedown is still very simple, though, despite all the screwdriver turning. After undoing all the screws, the upper receiver slides right off, revealing the hop-up unit that is set into a larger (metal) block that sets it against the receiver.
After finally making it to the hop-up unit itself, you’re greeted with the above. The two larger pieces are the drum portion of the hop (the first one sets the hop against the nozzle, and the second one is the actual drum portion that you turn). The pieces to the right are the hop-up arm itself, the hop-up nub holder (for lack of a better term), and the hop-up nub itself. Installing the Prometheus barrel is as simple as any other standard hop-up, and involves removing the barrel clip holding the barrel in place, sliding out the stock barrel, and inserting the new one. The hop-up rubber is a standard-looking black one and could easily be mistaken for a much cheaper and lesser quality one, although I’m sure in reality it’s made by the Elven blacksmiths of Rivendell under the light of a full moon.
Above is a closer look at the magic. The most obvious change from a “standard” V2 hop-up is the fact that the hop-up arm comes in two parts – the arm itself and a separate part that holds the nub. The separate part nub holder is flat where it meets the hop-up arm, and I believe this is so that it applies even pressure on the nub, which in turn applies even pressure on the rubber, and thus provides a more stable hop-up to the BB. Combined with the drum hop (which I find to be more precise and stable than wheeled hop up units), this results in a very stable hop-up unit. The drum itself is very stiff and holds adjustments solidly.
The one thing that became very clear to me during the entire process was the very tight tolerances involved in the build quality of each and every part. Every part mates together with other parts so seamlessly and cleanly. There is zero wobble or looseness in any of the bits. Everything fits together perfectly, and I think this goes a long way towards producing that famed Tokyo Marui performance that everyone raves about. One might argue that the TM SCAR-H is over-engineered, but the resulting performance compared to other companies’ offerings (and in particular compared to the easier-to-takedown VFC SCAR-H) speaks for itself.
The tighter 6.03 bore of the Prometheus barrel resulted in a roughly 30fps boost, bumping me up 330fps. Down the road I may or may not look into changing up the gears and motor to accommodate a stronger spring and kick up the fps to the 400fps level (I know Juicy is looking into this upgrade path), but for now I’m entirely happy keeping the entire thing stock. I’m pretty hesitant to mess with a platform I’m not 100% familiar with, and I don’t want to lose any of that fabled Tokyo Marui reliability. I guess time will tell what upgrades (if any) I’ll be doing to the platform in the future.
A quick peek at my current external setup (this was before the inner barrel upgrade, hence the short CQB length outer barrel). More on the external setup is to come once I get a certain optic in the mail (thanks in advance, Stealth, if you’re reading this!).