G&G M4 gearbox

[pete53534]

Ive picked up a used g&g m4 non blowback. I believe it is running a v2 gearbox. Would a v3 fit? If so what would the benifits be from replacing it. Thanks

[DaemonsWithin]

Re: G&G M4 gearbox

The ar platforms tend to use the v2 gearboxes pal. Easier to think of the versions as different platforms as opposed to potential 'upgrades'
The g&g gearboxes tend to be reasonably good as they are. Tinkering is always an option but as the old saying goes, 'if it ain't broke, don't fix it!'

[pete53534]

Re: G&G M4 gearbox

The charging handle spring has broken so need to strip the body down anyway and was looking at speeding up the rate of fire. Thanks for the info on the v2/v3. So whats best to do with a v2? Short stroke and gear set or would a faster motor be a better start. Also it has been run on an 8.4v 1600 battery. What would happen if i used the 9.6v 2000?

[Knaggsyy]

Re: G&G M4 gearbox

For rof high speed motor would make a considerable difference and also the high speed gears but while you've got it open you may as well correct the aoe look that up and yeah a 9.6v would make a difference but if you want more speed look at using lipos 7.4v unless you want to get a mosfet then use an 11.1v, lipos will also increase your trigger response as well as rof

[pete53534]

Re: G&G M4 gearbox

So are 7.4v lipos safe without a mosfet?
Sorry for the simple questions.

[Knaggsyy]

Re: G&G M4 gearbox

Personally I've upgraded my gearbox but I stick too 9.6v nimh as it performs how I want it too and don't really like lipos but my mate has ran his G&G on 11.1v lipos for the past two years and it's still going strong it will just cause more wear on the internals but 7.4v should be fine aslong as you look after it.

[Shizbazki]

Re: G&G M4 gearbox

Hi

If you want to speed up the ROF on the gearbox then i would recommend a high speed motor such as the G&P M120 high speed motor which i use in my MP5. If you have the GB open then i would recommend cleaning, regreasing and shimming the gears as that will increase ROF but also increase longevity. Grease wise use White Lithium Grease on gears and moving parts, non petroleum based silicone grease on piston head, piston o-ring and air nozzle o-ring.

Also to further up the ROF use LiPo batteries instead, some people are very against them, others think its the solution to all problems.

LiPos come in two flavours 7.4 and 11.1 volts, 7.4v is a safe Lipo bet as while it will increase your ROF it wont wear the trigger contacts through arcing too much, 11.1v will causing arching on the trigger contacts but the ROF will be immense (my mates WE SCAR L fired at 27 Rounds per sec on 11.1v lipos on stock gears), it will also wear the GB out faster. If you do want to use 11.1s then i would strongly recommend using a MOSFET, i use a GATE PICO AAB in my G&G TR4-18 on 11.1v Lipos.

Also if you do go down the LIPO route remember that you will need a different balance charger, normal NiMH chargers wont work.

The last thing you can do to improve ROF (though only by a tiny bit) is change the battery connectors from the normal Mini Tamiya connectors to Deans Connectors as they have less electrical resistance.

[sladgin]

Re: G&G M4 gearbox

For ROF gun, you need:
-- High torgue motor (aimtop is best), srsly highspeed motors sucks
--Speed gears (SHS) you can try to find gears with double piston streching
-- 3S lipol (+MOSFET ofc)
--weak spring M100 (max M110), if you want harder, you need to buy CNC gearbox

And that's all

[jonny lovegrove]

Re: G&G M4 gearbox

Them misinformations.

SHS high speed motor. This will basically stick you on 30rps with no effort and a 9.6v nimh, But you will want to open up the gb and perfectly shim it. And ensure the AoE on the piston is PERFECT. as the motor has bloody strong magnets and will strip everything in its path with very little hesitation.

[pete53534]

Re: G&G M4 gearbox

Thanks for everyones replys. Is there anywhere that anyone knows of where i can get a prepped gbox and motor combo that will slot straight in?

[jonny lovegrove]

Re: G&G M4 gearbox

not really, you'd be better sending it off to a shop with a load of parts.

[sj_asc]

Re: G&G M4 gearbox

So are 7.4v lipos safe without a mosfet?
Sorry for the simple questions.

Yes, in general. However its dependant on how much current you motor wants. High speed motors typically pull more amps, so the exiting wiring loom and trigger contacts have to deal with this and if they're getting hot and contacts are arcing hard then thats wasting you performance in the form of resistance and heat. I would strongly advise wiring a FET in the loom if you intend on taking the high speed route.

For ROF gun, you need:
-- High torgue motor (aimtop is best), srsly highspeed motors sucks
--Speed gears (SHS) you can try to find gears with double piston streching
-- 3S lipol (+MOSFET ofc)
--weak spring M100 (max M110), if you want harder, you need to buy CNC gearbox

And that's all

This could cause a whole chain of problems.
Firstly, AIM TOP being labeled as the best motor is only you opinion, there is a very large range of motors out there to choose from.
The biggest drawback with the nature of high speed motors is that they do draw more current, so less battery efficient. Torque is only really a problem for high speed motors that have ferrous magnets, motors like the SHS High Speed for instance actually have significantly more torque than some motors actaully branded specificaLLY for torque (Lonex A2 is just one example for embarrassment) thanks to the use of higher strength neodymium magnets. The only difference is that they pull more amps, get hotter much quicker and potentially can fail if that heat cannot be shifted in time (there are mods for this). It's also worth nothing that the higher strength Neo magnets are also more susceptible to heat damage (weakening the field, thus torque), so if heat is not managed properly you may struggle for pickup times.

Weak spring for high ROF builds - This is totally false, and if this advise is followed, someone could end up spending potentially a lot of money only to have parts fail almost immediately. The faster you go, the more you have to up the main spring rate to keep the piston assembly in time. If you are severely out of time, you may end up with complete lock up, stripped gears, piston, blown FET, damaged battery pack (lipo fire) etc. Pre-mature Engagement will severely shorten the lifespan of even the best of pistons, some gears will also fail at the bottom end as a result of this too.

Reinforced box is a good point in this case, however at M100 power levels not really worth the extra spend, however if that route were to be taken, it doesn't necessarily have to be CNC milled. G&G's V2 in general tend to bite the dust at around M120 rate, and or very high rates of fire, methods of shock reduction can be applied, but in all the failures that I have experienced with these, the default radiusing done on the cylinder window corners does not resolve the material (or lack of) weakness.

[pete53534]

Re: G&G M4 gearbox

Ok thanks. Alot to take in. Im beginning to think its just worth handing the gun over to a shop with my bank details and collecting it when its done as it seems to be a bit of a mine field.

[colinjallen]

Re: G&G M4 gearbox

Handing the gun over to a shop is probably the best idea; however, you need to be sure that the shop's engineers know what they are doing. Surprising as it may seem, not all of them do.

[pete53534]

Re: G&G M4 gearbox

Any recommendations in the west london or buckinghamshire areas