Hurricane V3/Systema mechbox, help!

[thePiRaTE!!]

Wow, where to start. Ok, the top.

I have a Hurricane V3 metal body and a drop-in Systema M120 for M4A1 mechbox.

problems:

- fire select switch on hurricane won't set systema mechbox to 'safe', only semi and auto will switch properly. They aren't making good contact, these parts are likely not compatible. Any ideas? Anyone else have this issue between these parts?

- metal screws provided by systema to attach pistol grip to mechbox are the wrong size (slightly too big for the threads on the mechbox) Anyone know the thread size of this mechbox so I can find more screws, or have any extras laying around?

- WARNING: the metal, one-piece hop-up is very unforgiving on the systema silent piston head set. The copper tube that fits into the plastic nozzle is a one-piece design on the piston head and is PAPER THIN unlike the Marui which has a plastic head, with the copper tube threaded in. The Marui is more robust ironically and I discovered this by shearing off the copper tube from my brand-new, unfired Systema silent piston head while putting the gun together. Thus begins my tale of woe, feel free to learn/laugh or cry with my story:

As many probably know, inserting the mechbox and closing the body is done completely differently on the Hurricane compared to a standard Marui body because of the one piece hop-up. It protrudes to far to simply close the top and bottom together like a Marui. The best way I've found is to insert the mechbox into the upper first, then slide the lower part of the body over it. This worked fine, but then I discovered the safety would not engage.

To isolate the issue, I simply tried loading the mechbox into the lower body as would be normal and discovered that at a certain angle, it works, but that angle does not align with how the body screws fit back in. This could be a critical failure if you intend to use a V3 hurricane with a systema drop-in mechbox, be warned. It should also be noted that the rear body pin of the hurricane is too thick for the systema mechbox. This required me to grind the pin down in order to have it fit through the mechbox.

Now, it was while testing the safety in the lower body that I noticed two things. The nozzle on my brand-new systema mechbox, wiggling freely and that the main adjustment gear on my hop-up was spinning freely. This was not good. So my little problem is now big problems. Luckily, I've gathered a few spare parts, so I swapped the cylinder and piston set in the systema with stock Marui parts. The mechbox is saved, albiet not as 'upgraded' as it once was. The hop-up rabbit hole got deeper. It turns out that the fake bolt carrier that covers the hop-up doesn't have enough clearance over the gears on the hop-up and took a little chunk out of two teeth on the middle gear. This created a dead-spot where the main hop-up adjustment gear would lose contact with the middle gear when turned to a certain point and then spin freely. After disassembling the charging handle mechanism, filing, bending and cutting the fake bolt carrier and associated parts down to prevent this happening again, we got clearance. Then we added a shim to the second gear and saved the hop-up too. Damn...

We decided to put the gun back together to see if assembling everything might cure the safety not functioning issue. It was at this time that I discovered that systema had provided the wrong screws.

FFS.

So, my gun is sitting... everywhere. I need the screws, the little pin that sits above the trigger that goes through the body and mechbox and the little metal motor plate disc that sits on the grub screw before I'm set to finish my gun that won't have safety. I'm so happy I could cry, lol.

Anyone been here/done this and have these little parts or helpful advice? Thanks - A LOT!!!

[Groombug]

I've had nothing but happy things with my Hurricane V.3 bodies. I have two, and have personally installed at least 2 more.

I run both my M4 and Bushmaster bodies with the old style Systema ProGear (black) and the new style Systema ProGear with FTK (HK special) gearboxes respectively.

1. Fire selector
- the problem may be that the circular disc on the other side of the selector switch isn't pushing the the selector plate properly. However, both pieces are manufactured with significant leeway. It is, after all, a circular disc pushing a round indent.

It may also be a problem with alignment. You can try dry installing the gearbox, lower receiver, motor and grip together to see if it'll perform all three fire functions.

It may also be that the gearbox itself has a broken trigger unit. I received one of these before in a second-hand gun. The trigger contact that is pushed by the trigger itself was broken in its tracks within the trigger assembly in the mechbox. This allowed the circuit to complete (thus fire) even with the selector plate on safe.

2. Grip screws
- I've never heard of this problem before. I've always assumed they were universal.

3. Nozzle and Hop Unit
- I've had no problems running stock TM cylinder head and nozzle, stock TM cylinder head and Systema nozzle, KM cylinder head and Systema nozzle, KM cylinder with KM metal nozzle, Systema cylinder head with KM metal nozzle, and Systema cylinder head with Systema nozzle.
- To avoid unnecessary damage, however, you should slide it in gently and horizontally. Because the gearbox is not secure or fully aligned yet, pushing hard (especially getting over those bushing humps) results in your gearbox nozzle accelerating to meet the metal hop at the wrong angle.

4. Body pins
The body pins are a little fat. I solved this with gentle hammering or by drilling out front and rear pin holes (including the rear gearbox hole) to make micro increases in the hole diameter. Be very careful doing this.

5. Bolt cover
I've had sticky bolt covers before... but no chewed teeth. I'm not sure how that would happen since the hop unit sits at the front of the bolt cover... You'd need to have put a lot of force in pushing the cover back forward to shear off gear teeth.

I've had nothing but joy with my Hurricane bodies. If you were in Toronto I'd invite you over for beers and gunsmithing... but alas, Calgary is not next door.

[thePiRaTE!!]

Thanks for that Groom. The beer and smithing would be most welcomed at this point!

1. I'll definately give this a try, as it ties in to 2.

2. I'll have to get some screws from a standard Marui mechbox and test their universality. It looked like the screw holes were smaller than the Marui ones on the bottom of the drop-in kit. There are four screw holes on the bottom and the kit came with four extra screws. Is it possible that systema assume you'll be using your own supply for screwing in the pistol grip? I'll definately test this by grabbing some standard screws for this purpose from my local tech.

3. This could be have been what I did. I did retract the charging handle fully however to ease in the insertion, but I had done this several times in trying to seat everything get the trigger working. I'll definately be aware of this in the future. It is worthy for others following a similar path here to note the frailty of the systema set in these regards.

5. The bend in the fake bolt cover where it aligns to the top of the slot (into the charging handle) comes to a 'v'. The top of the bolt cover and this bend travel within a hairs height over top the second and third hop-up gears as the cover moves to its end point. In my case, this piece wasn't shaped perfectly and made contact with the gears. The amount was minimal, but the effect was cumulative. It also had the effect of slightly misaligning the hop-up as it opened and closed across the gears. Its fixed now though. I think the classic 'lock and load' (ie pulling it back, and letting the charging handle go) may have been to blame. In fact, its probably a bad idea to do this with airsoft guns in general as a slight misalignment combined with the unrestricted force of the handle flying closed creates the potential for trouble, as I am proof of.

I'd add to my equation here that I am the second owner of the gun and modifications had been performed to the body by the previous owner to allow for the wiring to come out through the back. It is possible that the tolerances of a new hurricane may be slightly different.

Also, I've purchased a G&P front set to replace the barrel I received with the gun as I was experiencing wobble with it. I've found that the type of delta ring makes a big difference. The kind that came with the G&P (like a real one that wants to be tightened with an actual delta ring wrench) makes a totally solid connection. It really does feel like the barrel and upper body are one piece with this set, kudos to G&P. Now, I mention this as it makes me wonder if the hop-up is sitting as far forward as it might on another type of barrel. If it isn't, it might explain the whole slew of misalignment issues and broken nozzle. Having said that, mags seat into the hop-up with no problems, so I doubt thats it, but... I just don't know at this point.

Thanks again! More thoughts and insights welcome.