Well, I decided to put a thread adaptor on the MP5K. I ordered a King Arms standard threaded one and being steel it does look quite cool. I prefer the look of it to the MP5K with the tri-lobe adapter – technically an MP5KN – which to me makes it look like you’ve just ditched the stock on your PDW. I decided it needed to be tapped and threaded to allow a grub screw to secure it since there was the possibility that it could move when attaching either a suppressor or sound hog. In theory, a sensible decision. In reality, not so much.
The hole drilled quite easily with the indicated drill size for an M3 thread and I proceeded to tap out the hole. Just as the tap started to protrude into the threads that take the adaptor it snapped. Well, shit. I now had about 1½mm of tap sticking out either end. A pair of pliers failed to grip it and simply broke of the remaining bit of tap on the outside. The next step was to drill the tap out. Funnily enough, it turns out that taps are really fucking hard and promptly blunted the drill bit. The outside part was now virtually flush but a quick run over with a tungsten Dremel grinding bit took it down to a smoother finish. The only option was to do the same on the inside, wearing down the original threads until the broken tap was ground down flush to the depth of the thread. It actually now looked pretty cool with the interrupted thread. The outside is a bit the worse for wear but it’s hidden by the handguard when fitted so ultimately of little concern.
Of course, it turns out that the King Arms adapter proved to be an extremely tight fit anyway and with a reasonable amount of brute force is now more or less permanently attached. It’s going nowhere.
I still haven't finished the upgrades but having discovered the Gate PicoSSR 3 mosfet, which is absolutely tiny, I've ordered some direct from Gate in Poland, one of which will go into the K.
