The problem IMHO is that the MG3 has been too much liked, for the wrong reasons the way i see it, and that's why that old, outdated piece of metal has been able to stay in service up until now. The problem with the MG3 is that it's had this stupid, almost cultlike status around it in the Norwegian armed forces atleast, with it being "wunderbare Deutsche stahl!" and all, and the common misconception that "well, it must be the world's best machinegun since it's pretty much been around since WW2 - and the Germans loved it back then - and it's still in use!" - around my parts atleast, usually uttered by folks who have never fired any other type of machinegun.
Truth is, while the gun did work well for what it was back then, it's been superceded by a million better types of weapons and weapon-designs since then. The MAG being one of them. Yes, it's design from 1958 - no need to change something that proven.
I wrote up a longer post about the MG3 vs. MAG-based designs earlier on MP.net, but i can't find the thread now. I'll sum it up in short here;
Why the MG3 should be retired for good:
- It's design is far too complicated (the complete bolt-assembly for instance, consists of something like 16 individual moving parts, 13 of them being parts that the end-user needs to clean during maintenance - the basic MAG-design consists of two (2) such parts), leading to it being far too prone to stoppages; All those parts need to operate and be timed in perfect harmony for a shot-cycle to occur. If just one of those small parts are off, the weapon will misfire... not to mention what happens if you during winter get snow into a warm weapon, melting into water which seeps into the weapon and then refreezes.
- It has a way too far over the top rate of fire, leading to it having way too much recoil and thus being uncontrollable when firing (ie. reduced precision) and consuming way too much ammunition compared to what you need to achieve effect on the enemy.
- It has way too low built-in precision for what it should have, mainly due to the fact that the barrels are free floating and not screwed/clamped in place like on the MAG, but also because of said recoil/cyclic-rate.
These are all fundamental design-flaws that can't be rectified by simply pimping the weapon up with a more tacticool look... like giving it a coyote brown paint finish, providing a better- and adjustable stock on it, putting rails all over and some awesome optical sight on top.