JG/echo1 MP5 gearbox replace
 

This gun has a weak metal in the gearbox case, specially in the cold season.
After breaking 3 such cases made by JG/echo1 I want to replace it with a reinforced Element or Dboy.
Does anyone know if I will be able to fit a Gearbox V.2 reinforced with 9mm berings [Element] into this gun?

Or generally speaking what the difference between a MP5 gearbox case and standard v2 ?

An MP5 gearbox shell IS a V2.

yes, I know that
but I've seen v2 shells sold as MP5 shells, others as M15 and so on, so there are some differences?

some armalite V2s have slots cut in the sides so that the receiver can flip open, other than that they are the same

Probably because they come with the required selector plate. But otherwise they're the same.

I think Styrak has the most probable answere, and you might as well just get a reinforced v2 and downgrade the spring for winter. Less wear in the winter and strong enough for summer time fun!

thats why if you have money, dont buy a jing gong mp5. because the internals and externals aren't as reliable as ICS, G&G and CA, but i dunno bout CA's internal's as well eg. piston V2 would do the job for your mp5.

I managed to put the element gearbox case in the JG, but it needed some little changes: the trigger didn't fit and the case was not closing well.

THat happens with sub-par china shit. And it will happen with all your airsoft gear until you start to listen up to what the responsible users recomend. You buy what you think saves you cash, only to find out internet guy was right and now you've spent more replacing cheap crap.