KSC HK33K mini review (many photos)

[amateurstuntman]

Right, another one of my random "how to" things that noone is interested in. In the same vein as the two P226 threads I have posted.

 

The KSC HK33K:

 

Right out of the box it feels lovely, very high metal content including:

Receiver, sights, trigger, mag, stock, fire select.

The cocking tube is not metal which is a bit of a let down. It is also not compatable with Marui type metal cocking tubes.

 

There is a nice bit of engraving on the mag well

 

Here is a photo of the stock:

collapsed:

 

and extended:

 

It only has two positions but it is very solid, the back is metal with a nice rubber pad.

 

The fore grip is the same on all three versions, the differences are outer barrel length and a solid stock and bipod on the A2 version.

the Bipod is avaliable from Den for 63 USD.

remove the push pin and the stock to get access to the hop adjuster.

the hop is positive and doesn't unwind. The hop rubber is proprietary but seems to be stable and is at least partly responsible for the great accuracy I have experienced.

 

Stripping

Three push pins (foregrip, stock and mag release) will get you here:

You can see the clever battery holder with it's integrated connector.

[amateurstuntman]

We can focus on the area including the gearbox and motor.

Push the fire select up past safe into the vertical position:

the safety will then pull out to the left side of the receiver:

 

Undo the two screws in the base plate exposing the motor and the two screws holding the tabs onto the motor (I prefer this system to the marui tabs)

you can now pull out the motor

there is a spinning collar on the gearbox end of the motor

and a brass washer to maintain the correct separation from the gearbox.

 

A look into the pistol grip shows this:

the two screws in the bottom hold a plate that screws through the plastic into the gearbox and holds everything rock steady.

remove them and you will be left with this pile of parts:

You can now separate the gearbox and the plastic lower receiver.

 

A few things are immediately apparent:

the 'box is bigger than a v2 by a large margin

it is a two part 'box with the cylinder unit removable after taking out only three screws.

a lot of thought has gone into the design of this gearbox whether or not it works it is a thing of beauty.

[amateurstuntman]

Mech box

 

The 'box is nice and heavy and feels strong (more than strong enough to cope with the stock power)

All the bushings are the bearing type

The cylinder head incorporates the feed tube but not the hop:

Two screws remove the complete electrical system from the gun:

they are very neat and easy to work on but the micro switch looks like high currents would eat it and this reduces the options for upgrading the gun.

Three allen headed machine screws let you pull the upper and lower mech boxes apart:

 

We can now look at the two parts in detail:

 

Upper Mech Box

 

The upper mech box comes apart with six machine screws, it can be split while the lower part of the upper mech box is still fitted to the lower mech box.

 

There is no tappet plate in the convetional sense.

the nozzle is part of the piston and continues into the piston inside the main spring and into the spring guide.

inside the spring guide there is another spring that tends to push the nozzle forward.

when the piston comes back a lever on the nozzle catches on the back of the piston head it goes back with the piston for a while until the spring guide pushes the other end of the lever on the nozzle and releases the nozzle. The spring inside the main spring guide then pushes the nozzle forward, loading a bb and staying in the same place while the piston continues it's cycle.

 

It is a complicated system and it is heavy meaning the ROF will be low but that is not what this gun is about.

The thing fires from a sear and can be manually cocked so the "tappet system" needs to be separate from the powered system.

For it's purpose then it is an elegant system and works very well.

Here is a shot of the upper mech box components:

and here is a closer picture of the piston.

It is a brute, it has a large metal part to facilitate the two modes of opreation and a tab on the top to pick up the rod attached to the cocking handle.

 

 

nb when re-attaching the upper to the lower you have to push the little black button on the left side of the 'box forwards to get the trigger sears out of the way of the upper gearbox components.

[amateurstuntman]

Lower Gearbox

 

Three screws allow the lower gearbox to be split open.

 

There are 5 main parts in the gearbox, 3 gears, a tappet plate/cut off lever and a trigger group

 

The three gears are the biggest problem with this gun, they are proprietary and made by sintering which is where powdered metal is heated in a mould until it melts into one piece. It is cheap but the parts made by this process have fault lines and have bubbles throughout making them weak.

 

Bevel and Middle gears

Sector gear

The sector gear is a half tooth type and has a very promenant cam on it for the tappet plate/cut off lever and a large indentation for the trigger protrusion (more later).

 

Here is a pic of how the tappet plate/cut off lever interacts with the sector gear.

 

Same picture but without the switch in it to show the little hole in the plate that activates the microswitch.

 

The trigger group has three protrusions, one that acts on the sector gear to push the teeth out of the way and acts as an anti-reversal latch.

the other two act on the piston sear, one for auto, one for single shot.

Here is a photo, showing the trigger group and sear but not the sector gear

 

The action of these parts is very clever as in the same movement it disengages the sear and pushes the sector gear round a bit to get it out of the way.

 

a top down photo of the sear and sector gear before the trigger is pulled:

the sear is in the up position where it could catch the piston and the sector gear is in the way.

 

in this picture the trigger has been pulled and the sear is down and the sector gear has moved round so that the teeth are not presented to the piston.

 

very clever.

 

when you rebuild the lower gearbox it is difficult to get the trigger return spring into the right place, just put it back together and look into the front of the 'box where the switch goes and you will see the spring here.

 

just grab it with a pair of needle nosed pliers and move it to here,

 

Now the trigger will work.

[amateurstuntman]

Overall

 

I love this gun, I don't have a chrono but it is firing very low. 200 to 250 low.

But, you know what, it doesn't matter.

this gun fires from a sear, the piston is stationary in the same place every time you release the shot. Added to that the hop is good and the trigger feels good and this leads to a very good accuracy.

I can reliably hit a little 2 inch high bottle of sauce from an MRE at the end of my 22.5M long garden with this thing.

 

on single shot

 

This gun is designed for single shot, you turn on the electrics with a switch in the trigger guard and it cocks itself. You fire, it cocks itself. over and over.

When it is on automatic the sear is held down by the trigger and the gun fires like a normal AEG, just not very hard.

If it suits your style of play this gun is very very good. Except the gears. With such a complex piston I suppose it is good that the gears die but is still a pain, even then you can still fire the gun by turning off the electricity and maunully cocking it.

It then becomes a beautifully built springer.

The gears can be bought as spares from red wolf and den and in the UK wolf armouries <spit> have them at 15 quid each.

 

I would recommend this gun - sort of. There is now a Chinese clone of this gun, the JLS E01, it is about $135 from HK retailers. It is up to you, if you feel like rewarding KSC for their bravery in researching this new technology buy the KSC one, if you want to try it out and see if it suits your style of play buy the JLS.

 

I have two KSC ones and I like them.

 

Magazines

 

The mag is an 80 rnd steel double stacker. Feels very good. There are no high caps for it but that doesn't matter either, this gun is a single shot gun.

 

Mods

 

I had a PSG-1 stock around, no-one wanted to buy it from the for sale section so I chopped it up a bit and ground and filed some material from the inside.

Then I cut the battery holder off and extended the wires into the stock.

 

Now it looks like this:

 

 

I love it, when my bipod arrives I will start whoring photos of it around the picture threads.

 

 

Right, Any questions?

 

 

Stunt

[Mike_West]

Oh OK, is anyone able to check if JLS is built exactly like that too?

[dismemberd]

Well...you've got some editing to do, but other than that, it's great.

 

 

It is a little dissapointing how weak it is, and how complex and unique the gearbox is, but nonetheless, it's under standeable because as far as I know, nothing like this ha ever been done, and I wouldn't expect that they get it perfect the first time.

 

It's amazing that you actually figured all that stuff out, and how it works.

 

 

TBH i just skimmed through it , nut from what I skimmed, you understood it pretty well, and it's complex.

 

Thanks for the review

[amateurstuntman]

Yeah, I have banged out a couple of edits. I am not a natural typist.

I did the whole thing as one post at first, I forgot it only shows ten pics per page.

 

I don't have confirmation that the JLS one is the same but gunners says it is.

Slow he might be but he has a good reputation.

 

As far as understanding it, I am good with machines. Even then I spent a while pulling monkey faces when I took this to bits.

I am not so good with electronics and electrics.

I still can't figure out the electric section of this thing, The switch is simple but what is the resistor and capacitor doing on the side of the switch?

The cam only activates the switch for 1/3 of it's rotation and, as far as I can see this isn't enough for the thing to operate.

 

I have to open it soon for a new bevel gear <sigh> so I will try to work it out then.

 

Stunt

[Sale]

I was looking at the electric components also, and started thinking maybe they have hidden a FET inside the switch assembly.

 

-Sale

[amateurstuntman]

I thought that too but there isn't much room unless it is inside the microswitch housing.

the front is taken up by some fairly beefy contacts and the bottom is the on/hoff switch I desoldered the contacts and tried to dismantle the switch but I didn't want to destroy it and I got to a stage where I couldn't pull the switch apart any further without appling excessive force.

 

I was thinking about putting my own fet on it and a 9.6v stick in the stock to push a bigger spring but I don't think the gears would cope and until I know how the switch works I don't want to risk it.

 

Stunt

[Sale]

In that case the resistor and condensator could be part of an electronic brake circuit. When the micro switch is not pressed, the motor poles are connected via the resistor. A similar system (minus the electric components) is found on the TM PSG-1 and I think the G&G L85 has it too. It's necessary for pre-cock AEGs so that the motor stops the gears from spinning too long after the electricity has been cut.

 

-Sale

[The Communist]

Ok, not an internals expert, but I've gotta ask this:

Could I safely upgrade the FPS; 250 is a little low, and I think that is the only thing that is stopping me from selling my SG-1 and buying the H&K33K.

[amateurstuntman]

I'm working on that.

I am part way through the transaction on another JLS one.

When I have a whole new spare gun I will start monkeying about in the guts to pull more power out of it.

[DarkLite]

Whoa, necropost. Sorry.

 

From what I now know and have heard, the JLS differs in several ways:

 

1) Proper steel in the gears, not this retard sintered stuff. Honestly.

2) Some of the internal gubbins inside the foregrip are metal where they are plastic on the KSC.

 

I might actually pick up the JLS - the KSC is very hard to find now, as not many people want to carry it anymore. That is of course if it can take a spring upgrade.

[BigAl]

Have you made any progress on this yet mate?

[DarkLite]

IIRC his KSC box farked itself, so he replaced the lower receiver with a JLS one and slapped a wood kit on it.

[amateurstuntman]

Nothing died but I just wanted to get the best performance out of it.

 

I do have a hybrid of parts in the gun now.

Half JLS and half KSC.

 

It is lovely, the wood is so tactile.

I put a list of which bits are in it in the HK pictures thread.

 

I also worked out that the odd resistor and capacitor in the switch unit is for an active breaking circuit.

 

The cam is on for almost the whole rotation of the sector gear and only off for a little while, it needs active breaking to stop the gears overshooting and causing bother with the hand cocking system.

 

It is such a clever system I just wish it didn't have a piston head/nozzle system that was so prone to air leaks.

 

When I get round to it I will put the remainder of the bits into a (presumably bonk) compete gun and probably sell it cheap.

 

 

Just to add, the sliding stock on the JLS one is utterly rubbish. I am going to try to find out a way to use the (really good) sliding stock from the Escort MP5, it will fit but it has the wrong kind of butt stock. If I can get the MP5 rails onto the JLS butt piece then I will be chuffed.

 

 

If you buy a JLS one, get the solid stock one.

[PlasticMag]

Have you successfully upgraded?

[amateurstuntman]

Yes.

 

It shoots 311 every time and is a nicely accurate.

 

I just wish there was a way to have a metal cocking tube.

[BigAl]

Cool cheers mate. Think I saw th epictures of it in wood the other day, gorgeous.

[amateurstuntman]

Yeah. Thanks to Sale for putting me onto the active breaking idea.

 

I love this gun.

I think of it as a CQB sharpshooter.

[DarkLite]

I might pick up a JLS as I'm going to be in the UK soonish for Uni. If I'm limited to 1J I want something unique.

[Stag]

Greetings, Gentlemen.

 

Speaking of Necroposts, I've just got a KSC HK53, and within 3 mags stripped a gear. Is this something I've got to get used to? The thread seems to imply it's a common problem.

[amateurstuntman]

Short answer:

Yes.

 

Long answer, some sets of KSC gears are better than others, you might get lucky with the replacement sets.

[Stag]

Short answer:

Yes.

 

Long answer, some sets of KSC gears are better than others, you might get lucky with the replacement sets.

 

Cheers mate. Am I right in understanding that the JLS gears are made of solid steel?

 

Short of breaking up a JLS offering, is there any way to source those bits that you know of?