Okay so I broke my third MP5 metal body. Two ICS bodies and a CA. After the third time I really wasn't into forking out another 300 bucks for a body that was liable to break again.
What I did to fix it was pretty simple. The inside of the gas tube on the mp5 has a diameter of 5/8" exactly. I took a 4 inch piece of 1/2" copper pipe(5/8" outside diameter) and used this to connect the upper receiver and body together. I have to still put the cocking handle in the pictures shown but you can see how it works. There is no adhesives used yet and it is just friction fit. It will probably loosen over time and I will add a set screw or two.
To be honest I actually like this more than before. There is zero wobble of the friend end and it feels incredibly strong. If your not bothered by seeing a piece of copper in the cocking handle spot this is a great way to save $300.
---Can't put this in aeg solutions so can a mod do it---
Edit: I ended up putting two set screws in. Ill post pictures once its completely done.