After a long time of wanting this GBB version of the Scorpion since it came out, I decided to get one.

Appearance: As I pulled it out of the box for the first time, I noticed that it has a nice heft to it, even though it "only" weighs just over 1kg. I also noticed that the upper receiver had been pushed upwards out of alignment with the lower receiver. Pushing down on it, it snapped back into place. This issue would return, but more on that later. The Scorpion is also very small, only slightly longer than the M11, if both have folding stocks attached and folded.

Next thing I noticed was the feel of the upper and lower receiver, outer barrel, and trigger guard- they are plastic with a very rough sandpaper-like texture. These plastic parts, compared to the plastic body of the TMP/SPP, are much thinner and more flexible, and have a rougher texture.
The hollow grip is plastic too, but a very hard and strong plastic, that feels very nice to hold. It has a much finer texture than the other plastic parts.

Immediately after my first impression of the body, I got a surprise as I turned the gun over to look at the right side- I was expecting to find the ejection port, but found a mirror image of the charging knob from the left side. Huh? I then spotted the ejection port on the -top- of the upper receiver... apparently, the real Scorpion ejects the spent cases upwards (and probably forwards)! This was news to me.
The magazine release button is on the left side of the lower receiver, and pushing it in let me pull out the magazine. The magazine as a very odd, asymetrical shape, with a ridge running down the left side of the back. The magazine well is equally odd-looking, and soon enough, as I tried to put the magazine back in, I found out how difficult it is to fit the magazine correctly into the well. It's a very fiddly process in the beginning, but with some practice it's no problem at all. Also, the magazine locks firmly into the well with a loud "clack!", and will not accidently drop out.

The folding stock is full metal and seems sturdier than the M11 stock, but it wobbles just as much. It is also much quicker and easier to deploy; all you have to do is slap up with your palm on the part that sticks under the barrel, thereby unlocking it from the stock retainer/front sight, and swinging it into place, where it locks. To fold the stock in again, you squeeze the two bars of stock together at the base, unlocking it, and swing it up and forwards, and push or let it drop into the stock retainer/front sight.

Overall, the Scorpion's design isn't very ergonomic or practical. It's difficult to grip it properly by the magazine, and I can't see any easy or practical way to attach a sling. However, it does fit nicely in my mk23 holster from Redwolf. The strap that usually holds the grip of a pistol, will hold the magazine on the Scorpion, leaving the rear part of the gun sticking up above the holster. It actually looks pretty cool and is pretty practical too! Alternatively, you could get an original Scorpion holster, I have one of those on it's way too.

Testing: As I filled the magazine with HFC134a gas for the first time, I noticed the fill nozzle isn't parallel with the bottom of the magazine, rather, it points in a straight line up at the top of the magazine, so, make sure to line up the gas bottle correctly with the nozzle.

At first I thought the BB follower wasn't able to lock into place at the bottom of the BB well, but I later found out that it is- the BB follower locking feature is just very poor and very hard to engage.

Having filled the magazine with gas & BBs, I put it in the gun and pulled back on the charging knobs, a finger on each side. The charging action is not very smooth, unlike the light, smooth charging knob pull on my KSC M11. Having pulled the bolt all the way back, I released the charging knobs, and the bolt slammed forward again. Aha, so it fires from the closed bolt position, I had guessed on the open bolt.

I moved the selecter switch backwards to "1", gripped the magazine with my left hand with my thumb resting up on the side of the upper receiver, aimed through the open sights at the target and pulled the trigger.

Wack! Ow! The left charging knob flew back and slammed my thumb, so I moved it down, out of the path of the knob. I fired off a couple more shots, the report is loud and and the blowback is pretty hard. Then, the Scorpion started firing blanks.

I took out the magazine and looked at the stacked BBs, everything seemed in place, I put the magazine back in the gun and tried shooting; more blanks.

As you can see in the above picture of the front top of the mag, the BB well is split into two different pieces of metal near the top. Between these two parts there are several slight seams and gaps, and the BBs tend to jam there.

However, by removing a screw on the top of the magazine, the upper metal part can be pulled up and off (it's pretty tight at first), and then these troublesome seams and gaps can be easily smoothed out with, for example, a very fine needle file. After this, the jamming and dry-firing problem is gone! Or so I thought. After yet more testing, I found out that the real problem was my hand that gripped the magazine. The BB follower easily gets caught on my fingers, and then the whole BB stack jams nice and tight. By simply not wrapping my fingers tightly around the front of the magazine, just leaving some space, the problem is now finally and utterly gone! I don't know if seams and gaps really had anything to do with the jamming, but I think so. In any case, if you smoothe out the BB well a bit and don't squeeze the front of the magazine, you shouldn't jam.

Running out of HFC134a and the local airsoft shop closed for the weekend, I dared using HFC22 for further test shooting. Luckily, the Scorpion seemed to use this gas without problems at all.

Having had plans to detach the stock, I was a little dismayed when I found that the folding stock wasn't readily detachable. The folding stock base isn't detachable at all (as it holds some internal parts in place with two screws), but the wire stock itself can be removed easily with the help of some tools.
I think that the scorpion looks very nice without the stock, and can be used more like a handgun than an SMG, but... as I tried firing it again without the stock, the upper receiver would start getting knocked out of alignment with the lower receiver. In the beginning I blamed the overly hard recoil because of HFC22, and a very weak rear part of the lower receiver, the part that goes up and holds the upper receiver in place. This part is indeed very weak and bendable, with an open seam in the middle. The open seam is necessary for total takedown of the lower receiver/trigger mechanism, but I glued the seam firmly shut with composite epoxy glue, making the rear end of the lower receiver stronger and stiffer.

However, to my dismay, this didn't cure the problem- but I found that putting the folding stock back on, the problem vanished. Very clever yet annoying, I thought, using the folding stock to make the design sturdy enough for the strong recoil. With the folding stock in place, either folded or deployed, the upper receiver is never knocked out of place, even with HFC22 gas. So, no gluing is necessary, just leave the stock attached.

Also, the bolt locks back after last BB fired. To release the bolt, you pull back on the charging knob a little, and the bolt smacks into place, ready to rock n roll again. :)

Performance: As for the actual performance of the Scorpion, I have been comparing it extensively to my M11 and SPP, and using only HFC134a gas (that I bought after the weekend). This has led to some interesting results.

First of all, I found the Scorpion to be more accurate than the other two, but the range is a little shorter when using .25 BBs. When using .20 BBs the range becomes more like the other two, indicating a lower power, or a gentler hop-up. I find that at long range, the shots from my KSC guns tend to often hook and/or fly upwards (regardless of hop-up adjustments), while the shots from the Scorpion have a very even path and drop-off.

As I tried using low-grade "Gold Fire" BBs in the Scorpion, I found out that it has a very fine tolerance, and the uneven BBs will consistently jam in both magazine and barrel. Using high grade BBs, there are no such problems. My "high grade" BBs are currently Power Bees, but I hear Excels are better... perhaps using Excel, there will be no jamming in the magazine at all?

I did a lot of target shooting on both semi and auto with all three guns, to compare their accuracy, and I intended to include scans of the targets in this review for comparison. But I found the differences to be surprisingly small, so I won't bother.

At first, the accuracies turned out the way I expected: The SPP performing like a sawed-off shotgun, the M11 having good accuracy, and the Scorpion having even better accuracy. But as I did more target shooting, it became apparent that they all had good inherent accuracy, if they were to be fired fixed on a bench. The differences in performance lies elsewhere.

SPP: With it's very blocky iron sights and hard blowback kick, this baby is hard to fire accurately, but with practice and a better scope attached to the optional scope rail, the groups can be tightened right down. The inherent accuracy is fine!

M11: During these tests, I have found out what firing from the open bolt position really does to the accuracy. Throughout the tests, the M11 would consistently hit higher than where I aimed, and I thought it was because of the very basic iron sights. But at one point, I took out the magazine and racked the charging knob, aimed the attached laser pointer at the bullseye, and pulled the trigger. As the bolt flew forwards, the laser dot jerked wildly up and right, then down and left as the bolt slammed home. I tried gripping the M11 much tighter, but the laser aim did exactly the same as before. Even with the stock extended and shouldered, and gripping the gun very firmly, it did the same, much less this time though. I hadn't thought the open bolt position would have that big an effect on accuracy.
Scorpion: Despite it's very hard blowback kick and very basic iron sights, this gun is surprisingly easy to get some very tight groups with, even without using the folding stock. Even when all three guns were aimed very carefully from a rest, the Scorpion is definitely considerably more accurate.

As I don't have access to a chrono and I didn't have a soda can in the house, I had to find a different method to measure the power. I decided to use a bar of soap... :)

Surprisingly, still using only HFC134a, and .25 BBs, the Scorpion actually made a bigger crater in the soap than both the M11 and SPP. The Scorpion also sounds like it shoots harder, a loud, sharp BANG on single shot, and a very aggressive and loud "ratatat" on full auto. It sounds much better than my M11 and SPP. :) The Scorpion's high power means that the shorter range must be due to a less aggressive hop-up than the KSC guns.

As for cycle speed on full auto, I can't really tell any difference between the SPP, M11 and Scorpion. They're all up there in the high RPMs, which is faster than I expected for the Scorpion.

Gas efficiency is fair, if the magazine is allowed to warm up for a couple of minutes after charging it with gas. At 20 degrees C, I get one full mag's worth 29 BBs on full auto, plus about 8 full auto shots, then a few more with severe cooldown before the gas is finally gone. These numbers are of little use to other people, though... when reading different reviews of the same gun, I find the gas efficiencies to vary wildly, either due to differences in the guns themselves or the temperatures or the brands of gas used, or all of the above plus other variables. But, the Scorpion seems to be fairly efficient, however it uses considerably more gas than my SPP and M11. This must be the reason for the higher power, more gas used per BB.

Upgrades: There are still very few upgrades for the Scorpion, but the ones that exist are very useful. DEN has the following things: Wood grip, two different threaded metal outer barrels, and a TN inner barrel.

Before I received the Scorpion I was thinking of getting the wood grip, but I think the stock plastic grip is surprisingly nice.

A metal outer barrel is an absolute must, though. It feels and looks so much nicer than the very plasticy stock outer barrel. So far there are two different metal outer barrels: One from Maruzen with the suppressor threads at the base of the barrel, and one from KM with the treads at the tip. I reckon the tip-threaded barrel allows the stock to be folded while having a suppressor attached, which the base-threaded barrel does not.

I got the base-threaded one, and it makes the Scorpion look much nicer, but I'm going to get the tip-threaded one too, as it seems more useful for fitting a suppressor. And I really can't wait to put a suppressor on the Scorpion... because it's so damn loud, and it'll also look very cool indeed. :)
Hopefully, there will be a metal upper and lower receiver available sometime, they would really transform the Maruzen Scorpion from merely a very great GBB into a super-great one!

As for high-flow valves, the Scorpion really doesn't need them! It already uses plenty of gas per shot, and if it used more, it probably wouldn't be able to empty a single magazine on one charge of gas.