Maruzen’s Interdynamic KG9 Full Auto NonBlowBack
Ash Nicholls

Stock Specifications
Model Maruzen’s Interdynamic KG9 Full Auto NonBlowBack
FPS 88m/s (0.97 J)
Length: ???mm
Weight: ??? grams

Ammo capacity:

80 rounds

KG9 Full Auto NonBlowBack | KG9 Full Auto GasBlowBack

Firstly a big thanks go out to Josh Horowitz of who kindly supplied the movie screen caps and stills for this review. You can find links to buy Big Trouble in Little China here (I highly recommend purchasing it). -Arnie

Introductions Ok, so 'KG-9 CQB Assault Carbine' is a bit of a gobful, but short of  “glorified monstrosity” I couldn’t think of a better moniker. Besides that’s what it is: not quite the machine pistol it started life as, and not quite the Assault rifle it aspires to be. It’s also a NBB, external feed gasgun.

That’s right, one of the “airsoft throwbacks”. One of those “obsolete” weapons that the Tokyo Marui-ites want you to forget about. Well knackers to that, because this thing is every bit as good as, and in terms of build better than anything TM produce today.

The model in this review is my personal skirmisher which is equipped with an extended barrel and a folding stock, and is now the only KG9 in my collection (having let the KG-9 GBB go to a better home where it’s not used for shooting cockroaches; be nice to her, Taeko)

Construction The Maruzen KG-9 is faithfully modelled after the classic ‘80’s pimp-gun that shares it’s name (1). Solid doesn’t begin to describe it: the vented barrel shroud, bolt cover, receiver, trigger, magazine and mag. catch on the base gun are all metal. The grip and mag housing are very tough ABS plastic.

The internals are all metal levers in a plastic housing. The whole thing is finished beautifully with a set of sling mounts moulded into the coachwork for good measure. The after market parts for this gun are superb (2).

The folding stock has a heavy cast zinc base which bolts to the back of the receiver and grip, and the stock itself is made of steel. The barrel extension kit consists of a machined brass barrel and a spun aluminium shroud with a guide bearing fitted at the muzzle end.

Operation After the fashion of all BV guns, the KG-9 operates on a short-stroke blow-forward principle. A follower picks up a bb, gas pressure forces the bb against an o-ring forming a seal (3). The whole barrel is pushed forward until the o-ring reaches a slightly broader point in the barrel guide, allowing it to expand and the bb to progress (rapidly) down the barrel. The barrel returns, picking up the next bb.

The KG-9 has a selective fire trigger (4) and therefore is incredibly simple to operate in both semi and full auto. Also, due to a rather sweet valve system, this is actuated in line with the trigger, so no nasty linkages to mess around with (5).

Magazines are spring fed and hold 80 rounds. The gun has a slight recoil due to the reciprocation of the barrel, which increases with the extension fitted, although it remains almost insignificant in terms of affecting accuracy.

The beast will feed off pretty well anything you choose to pump through it (6). I personally use either regulated C02 or Compressed air fed from a proprietory airsoft tank (Sherman M4) at a feed pressure of 8-9kg cm-2.  

Performance Right, this is where all the sage and wise AEG owners nod their heads and mutter about hop-up. Un-hopped, the KG-9 custom shoots straight for 35-40m, before dropping off (stock performance is probably about 25m). Yes, that far. The gun was chronoed at 88ms-1 using 0.25g bbs, at a feed pressure of 8kgcm-2. That’d be about 0.97 J. Oh lordy.

In the field, the gun consistently outperformed all of the Marui SMGs and a good proportion of the Marui longs. Accuracy is excellent, perhaps due to the lack of hop. Admittedly, lugging a gas supply into the field isn’t everyone’s idea of fun, but once you get used to the feel of the tank being there, the only real disadvantage in skirmishing is the magazine capacity.

Hi-caps can be fabricated(7), however, and frankly with two spare clips you have 240 rounds to play with. In CQB, this should be more than adequate. I prefer this gun to my electric rifle(8) already, and will probably rely on it as a primary from now on. These things are not to be underestimated.

One delightful chap who described me as “the strange foreigner with the obsolete gun” was so confident that he broke cover 25 yards in front of me thinking he’d be ok. Naturally, the ‘9 was pointable and accurate enough to draw a line up him, and then pop his mate who stuck his head up to look from 5m behind him. Marvellous!





4/5 No hop. No problem.

Value for money

4/5 second hand Japan: lovely prices.

Upgrade potential

3/5 basically limited to what I’ve already stuck on her

Build quality

5/5 Luvverly metal everywhere.

Overall Potential

4/5 powerful, accurate, reliable, compact, pointable. It’d be perfect if it weren’t for that sodding great airtank…


1 The Interdynamic KG-9, and it’s stablemate the Tech-9. A pair of guns aimed at the criminal end of the market, one feels, when you consider the advertising blurb included such features as a muzzle that could fit an improvised suppressor, and finger-print proof grips. Fortunately for me, Taeko covered all the detail in her review TOP

2 Beautifully made, but relatively sparse in number: Extension kits, folding stocks and silencers, mainly. TOP

3 As in an airtight seal, not the popular marine mammal. Pay attention at the back! TOP

4 Half pull for semi, long pull for full auto. TOP

5 I am currently in the process of writing a book entitled “Why all you bastards went bankrupt” detailing the decline of the Japanese NBB airgun industry due to crippling development prices incurred by using an industry-wide standard minimum of 98 inches of cast zinc linkages in their trigger assemblies. TOP

6 Disclaimer: any injury, loss or dismemberment arising through the use of pure oxygen, butane, etc. in classic airsoft guns is not my responsibility. I may find it in my heart to supply a jam-jar for the burial. TOP

7 But it’s a hassle, and chopping up a rare mag, to build a useless new one is not a good plan. TOP

8 Possibly because my electric rifle is a Famas/shotgun combination which weighs 5kg and is a sod to lug around indoors. TOP

-1, -2 Those weren’t footnotes, you muppet, they were SI notation.    

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Last modified: Wednesday, May 9, 2001 9:37 AM copyright 2001 ArniesAirsoft
'Big Trouble in Little China' imagery is copyright John Carpenter.