Military Policy & Weapons/Shoulder mounted machineguns
Hi! In Fallout New Vegas downloadable content there is this shoulder mounted machinegun you can pick up. It uses 10mm ammo. I've attached a picture of it. Does this weapon look/sound practical?
I generally only answer questions about real-world weapon systems, but I'll make an exception here. First of all, that picture shows a minigun, which is different from a conventional machine gun. It houses an electric motor that drives multiple rotating barrels (like a Gatling gun) which permits a huge rate of fire -- in the neighborhood of 6,000 rounds per minute. The rate of fire is so great that you don't hear individual gunshots, not even rapid-fire shots like you would hear from a machine gun. It's one long, loud buzz. There are lots of videos on YouTube; check them out.
Your question was, would a shoulder-mounted weapon like this be practical? Easy answer: no, not by any stretch of the imagination. It's not the recoil that would be a problem -- a 10mm round isn't very big; it's a pistol round. But the vibration these guns put out is indescribable. Carrying a weapon that size on your shoulder is already going to affect your balance (that's a couple hundred pounds we're talking about), and with the immense vibration, you'd have a hard time even standing up, let alone trying to hold the thing on target.
Secondly, you'd never be able to carry enough ammo for it. 6,000 rounds per minute, that's 100 rounds every second. Imagine carrying the weight of hundreds of rounds of ammunition (on top of the weight of the weapon), and even then only having enough for a few seconds' worth of fire? Lots of effort for a short period of firepower.
Finally, what would you need it for? A minigun is really best suited for an aircraft or vehicle to carry. Something that can provide a stable platform and can carry a sizeable amount of ammo for it, and as such, that's where you tend to see them in the real world. A shoulder-mounted minigun definitely looks awesome, and that's why you'll see them in a video game, but it's not practical by any means.
Hope this helps.