I will admit that I have not fired the 7.62 Minimi, and I am aware that it was intially developed for this round, however I do think that using a round of this size in a weapon as small as this is asking for trouble..
OK - it has a hydraulic buffer to take the edge of the recoil, but I would think the thermal characteristics would be fairly horrific. I would bet that bits would be glowing before not many rounds.
You would have to be VERY careful about the rate of fire, so ok for SF, but I don't think it would work as a general issue squad MG..
It's possible, but whats the point? The SF types need heavier firepower in a portable package. Regulars don't, because they have a lot more options for fire support, and don't NEED to scale down (with all the associated problems it entails)
Yes a scaled up Minimi is a gucci piece of kit, but a full sized M240 or GPMG is still going to be more effective for sustained fire roles.