DISCLAIMER: Airsoft part only, utterly useless in any real firearm!

It started as a joke, then became a bet and in the end turned into surprisingly working project:

Someone offered me an MP5 hi-cap he had no use for, and i wondered, if i could find some reasonable application for it, since i never had an MP myself…
Then i got my eyes to my old AKSU, which is already a “project gun” ( = mess of random parts of mostly untraceable origin) and after a few beers I thought I might turn it in a pseudo “PP-19 Vityaz”
Sobering up the next day, I decided that the conversion must be fully reversible and drop-in:

So there it is!

I actually went through multiple iterations, and bought more MP5 mags in the process, noticing the dimensions tend to vary a lot. The final iteration is optimized for best fit to a CYMA “coupled magazines hi-cap” with fancy fake rounds on the second mag's body, yet it works with other types as well - I already tested it in the field last weekend.
The final version is from ASA with some acetone vapor treatment, also works great from PETG

Since I noticed that some fields started enacting some rather strange rules about “SMG and AR” class, I think it will come handy soon…

A piece of 3mm rod/wire/screw is needed for the magazine catch lever, as well as a spring - i used a 7mm diameter one from a "random springs box" from a hobbymarket.

PS: I already got some EVO mags as well, so the heresy will go on soon :D