The only upgrades I did to my K was a longer inner barrel which extended into a custom machined silencer. I simply took a stock m4 length inner barrel and hacked it down to just under 300mm, cleaned up the edges with a dremel and threw it in. Damn thing shot straighter than my M4 with a 6.03 tightbore! It was a bit more work to switch the barrels out than a regular MP5 or M4 but nothing tricky. I never did notice the "tin foil" effect mentioned above although it was only disassembled once.

I even made custom adaptors so that regular MP5 full and retractable stocks could be mounted onto my K with ease. I baught it thinking they would simply slap on:hammer: I hated the look of the m4 slither stock on the K's as some do so I figured I'd make a mold and cast a piece for it. Still have the master mold for that adaptor also but I just sold the gun:rolleyes:

IMPORTANT: Make sure you locktite the small set screw on the left side selector switch! It works it's way out then next thing you know the one selector switch has disappeared.

I upgraded mine myself:
I added a longer barrel (in the silencer ) and pinched holes in the piston head to avoid fps headaches.

I also rewired the thing for an external battery, and I have to say the original wiring (for the ak battery) uses parts and cables in the body that make removing and putting back the mechbox a hassle, so I just got rid of them; instead of going all the way to the front end, the wires go directly out the rear body cap thingy ( I removed the fuse ).

To mount the motor I usually use needlehead pliers, and I replaced the cables with longer ones.
it's probably a good idea to rewire with very smooth silicon wire but I dunno.

and that's it!

I added:
sp110 tring
torque up gears
eg1000 motor
bearing spring guide
shims+bushings
polycarb piston
unported cylinder

no sweat colin - it wasn't supposed to be personal.

I was being childish, so I erased it and took a breather. Sometimes the internet brings the worst out...