Best battery / motor for Systema gearbox box?

[panda86]

I'm building up a new AEG, and I was planning to get a Systema complete gearbox (M100) with the turbo motor (blue ends / black body). It says it's for the M16A2, but I would assume this would fit in any metal body M4?

I've got a crane stock mounted 9.6 mini 1500MAH nunchuk battery, will these work OK with the Systema gearbox / turbo motor? I'm not trying to build a high ROF monster, just something reliable and consistent performance.

What kind of FPS should I expect with this combination? Anything better than the stock TM M4 is an improvement, but I wanted to see what FPS I would get.

Will the same batteries be strong enough if I got the Systema M120 gearbox?

Thanks for the advice

[ShelledPants]

If it says it's for an M16, it's because it's cylinder has no port. You should look to either getting one for an m4 (with a port near the back of the cylinder) if you're going to be running it with a barrel shorter than an M16's.

An M100 should be 100m/s which is roughly 360-380 fps. Perfect for Canada outdoors.

That battery would be fine for the M100 box, but it might struggle with the m120 and turbo motor.

[Skladfin]

it wont struggle at all.... =\

the systema M120 mechbox comes with the Magnum motor, that shit is incredibly strong. it will probably pull a M120 with 7.2v battery no probs.

you should get around 330~350ish FPS, i say that because you probably dont have a perfect airseal. It's an TM M4, its expected that it doesnt have a perfect airseal

[panda86]

Thanks so far. It will be a metal body with a G&P metal hop up, not sure if that would affect things.

[Skladfin]

use prometheus airseal hop up rubber, the purple one.

[damage]

Send it my work table and I tune it up for you.

[Dusti69]

are the systema gearboxes the ones that are stamped SB on the side?

[damage]

Originally Posted by Dusti69

are the systema gearboxes the ones that are stamped SB on the side?

No Systema gearboxes had a stamp "SYSTEMA". SB stamped gearbox are JG I believe.

[ILLusion]

Being for an M16A2 only means that the gearbox will be rear-wired. It may or may not have a full cylinder, I've actually seen both full cylinders as well as ported cylinders for them as they are all sold as "For M16A2 / SR16", which are rear-powered guns. You may want to check with your source to find out exactly which cylinder it comes with. Ask if it comes with a "Type-0 Cylinder" (unported) or a "Type 2" (ported for 363mm inner barrel).

However, that rear-wiring will be short for the Crane stock application (as it typically clips on to a wiring harness extension that runs through the full stock.

You could splice the Crane stock wiring to the leads coming off the back as recommended in the crane stock manufacturer installation manual, but I don't recommend that. Splicing leaves bulky wrapped joints that are prone to damage. I've seen several shorted out batteries due to poor splicing or compromised joints due to jamming gearboxes and wiring in to metal receivers and running them through tight buffer tube joints.

Your best option that I would recommend would be to run one piece new wiring from the switch and motor all the way out to the back of the buffer tube - the easiest and most cost effective way of doing this is actually getting the M4A1 / S-System gearbox which has front wiring. The motor wire is long enough that you can just flip it around to run to the back and the only wire that needs replacing is the positive wire running from the trigger switch to the front (which now needs to run all the way to the back.)
Otherwise, if you get the rear wired wiring harness, you'll need to replace both of those wires with new ones as well as a new motor connector.

If you're not trying to build a high ROF monster, explain why:

1) You're running a 9.6v battery
2) You're using a Turbo motor.

Both of those lead towards high ROF - the combination of the two plus such a low velocity spring = very high ROF. High ROF setups are not conducive to reliable and consistent performance, but it does lead to low trigger times.

Expect to see 330-360fps with that spring.

The same battery may be strong enough if you get the M120 gearbox as it has torque up gears, but expect ROF to be slow and lifespan to be short. You're better off getting a 600mAh Ni-Cad mini pack, as Ni-Cads have higher cranking power than Ni-MH does.

@Skladfin:
Your comment is unfounded - the M120 mechbox does NOT come with the Magnum motor. The M170 set does.

[m102404]

I'll guess 347fps w/ 0.20g bbs....what do we get if we win?

If it's a 9.6v 1500mah mini made up of 2/3A cells, the battery should be able to pull a M120 with a TM EG1000, System Magnum, Guarder Infinite Torque Up, G&P M120 High Speed. It should also work with a new stock CA motor (but I don't really trust them for longevity...). Those are the only motors I've used in my own rifles with that battery/spring combo. Obviously the Magnum motor rocks. Don't expect the battery to last all day if you shoot a fair bit.

I don't know what the gear ratio is in that Systema complete mechbox...and sorry, I'm too lazy to look it up.

Why would you put a mini battery in a crane stock? Even the G&P crane takes cells larger than 2/3A and many take large cells (which can maintain a good dumping of power and tend to last all day and then some, at least for me).

Best of luck...let me know if I win the FPS guessing game (and BOO to those who guessed a huge range... ).

[panda86]

Thanks for the info so far guys, really useful. I'm lost when it comes to combos other than stock.

Ive already got a VLtor replica stock (the kind that holds CR sized batteries). I'm going to modify it to take a 9.6 1500 MAH mini nunchuck because I have 2 of those already. I didn't want to get all new batteries if I had some that worked.

I'm actually leaning more towards the M120 gearbox so that I can get closer to 400fps.

Illusion, I wasn't planning on using 9.6 large size batteries so I thought that might affect ROF. I just wanted to keep the weight down if possible by using existing mini batteries, but I undertstand it's moreso the voltage rather than MAH rating.

I just noticed that some Systema gear box packages come with the motors and some don't. I just assumed they packaged them that way for a reason.

That being said, are there any other "complete" drop in gearboxes that will get me towards 400fps (but below for fiekd reasons) that are more affordable and can work with my battery situation?

Thanks!

[ILLusion]

Okay, that makes sense - the VLTOR is not a Crane and can only hold 2/3A mini cells.

I recommend you DON'T go with a Turbo motor if you're cranking an M120 box with mini Ni-MH batteries. The Turbo motor sacrifices torque for RPM. That's not acceptable in your scenario where you're already lacking torque as it is. Reducing it further will kill your batteries. Your start up trigger times will be horrible, however, your sustained fire in full auto will slowly pick up the speed to high ROF. You'll actually be able to notice the pick up within about 5 shots.

I wouldn't even recommend the Turbo motor be used with M120 boxes even if you were running large batteries. It's a great way to put a lot of stress on an expensive motor and your batteries.

As far as your battery solution goes, if you HAVE to get it up to 400fps, get an M120 box and see if that ROF is acceptable for you. I use to run a similar setup for two whole seasons and I found the ROF to be more than acceptable, although running the same setup with a sub-C pack yielded very noticeable increases in performance.

If you're looking for more affordable, I believe Guarder is making complete boxes now as well, but I don't know what gear ratio they're using. I only know Systema M120 boxes have torque up gears.

[panda86]

Thanks Illusion for the info.

I'm going to modify the Vltor stock to hold mini batteries, and use the batteries I have. Again, not looking for huge ROF, so I'm willing to not use a Crane stock with large cells at this point.

I was only going to get a turbo motor since I see that sometimes come with the Systema package. Would any of the motors that M102404 mentioned be OK with my setup? (TM EG1000, System Magnum, Guarder Infinite Torque Up, G&P M120 High Speed).

I haven't entertained the Guarder gearboxes, but I will. I just want a plug and play solution, I'm not planning to tune up every little part.

Thanks guys, I'm learning a lot from this thread!

[ILLusion]

You can run the Systema M120 fine with a TM EG1000.

The Magnum will run it fine as well.. probably better, if you can swallow the price tag. I have no experience with Guarder motors, so no comment there. As for G&P... they should be okay, but I'd personally stick with TM for reliability purposes.

[panda86]

Thanks Illusion! Much appreciated.

Holy crap, I didn't know the Systema Magnum costs that much... Just looked up the price :P