Of all the interesting pieces I have owned, I have 2 guns on my "must have" list. The. 25mm Petaux and a Minigun. I have fired several and just never owned one. Of the Minigun, I have spent some time on General Electric, Ciener, DeGroat, Dillon and Garwood, and like them all. When they are tuned up with good ammo they just plain run and run and run.
The ultimate gun I have is this one, with the appropriate and functional happy switch. The ultimate gun I would love to have is Hitler's buzzsaw, the MG 42. And a .303 BREN. And a factory Russian AK 74 select fire, and....
A "Pig Gun" - an M-60..... I was with a Mechanized Infantry unit, so we had a few mounted on every track, plus each squad carried one when we were doing Combat Assaults (Choppers) or humping up & down the hills in the Central Highlands in '68. Other than being a bit heavy, it was accurate, pretty reliable, one-man portable & could definitely tear things up.
in the realm of reality it would be a Beretta 93r. Outside of the the automatic grenade launchers we shot in MP school would be fun. I cant remember the model. M213 maybe.
One of those 10mm rifles from Aliens would be nice.
I've considered getting a dealers license & trying to convince local LEO that they need a FN P90. I rented one in FA at Scottsdale gun club a few years ago, what a hoot to shoot. I have a SBR PS90, not quiet the same.
Runnerup would be a M249. They are so fun to shoot & 5.56 is relatively reasonable to shoot.
William J. Hughes spoiled the fun on May 19, 1986.
MG42 I guess, though a vickers would probably make me just as happy in a pinch.
there are really too many to list, MP40 is up there too. a SAW or M60 or M2, hell I'll take any of the above if you're buying.