I would build a totally custom weapon based on the HK416.
I would invent a new caliber - let's call it "Jenny's Super-Thirty". Take the 10mm case, neck it down to .30 cal and load it hot enough to equal the 7.62x39 but faster, lighter, and flatter shooting. (Just humor me on this....not sure if it's practical). The bullets for this round would weigh 110 grains and have tungsten cores and would be black teflon-coated, just to really tick off the antigunners!
The rifle itself would take Surefire-style quad stack magazines, so each mag would hold about 60 rounds. I would want an integrally suppressed short barrel (10") flat top HK416 upper with a holographic sight that can turn into a Gen IV night vision unit (hey, it's fantasy, right?) and backup tritium iron sights. The rifle would of course be select fire, and it would come with a spare flat top 24" upper as well chambered in 5.56mm and capable of mounting a long range scope.
For appearances sake, I would have the rifle come in a matte stainless finish. The pistol grip would be shaped like a 1911 grip, and would be able to use 1911 grips. Of course I would have a custom "silverwood" laminate grip with my initials in silver inside a silver laurel wreath. The folding stock on the rifle would be matte stainless as well. Handguards, cheekpads, etc. would be made of "silverwood" laminate.
Yep... I got this one down!
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