Man-Portable Mini-Guns?

[Bathawk]

Hello, I have another "Gun Question"

DO man-portable mini-guns exist? They have always been popular in action films like "Predator" and "Terminator 2: Judgment Day" But I read somewhere (at least in the "Heroes Unlimited GM's Guide" that such weapons are pure fantasy and not viable, at least as a "man portable weapon"

Og course that was years ago, and science marches on. I recently started thinking about this again after watching "Captain America: The Winter Soldier" where another "minigun" was used in the bridge scene

Even if a true "rotating barrel gatling-gun" like weapon doesn't exist, what would be the closest equivalent? Meaning a man-portable weapon with an obscene rate of fire and the ability to carry enough ammo for more than just a few seconds of fire

[Anthony]

The core problem with a man-portable minigun is that, in any useful caliber, it's too heavy for a human to practically carry. The lightest minigun I'm aware of is the XM214 Six-Pak, which has a total system weight of 85 lb (including a thousand rounds of ammunition); it's a .223.

If you want a man-portable weapon with an absurd rate of fire and ammunition capacity, I suggest the American-180 or derivatives.

Actually, there's supposedly something called the XM556 out there, which is a .223 minigun in a human-manageable weight, but I have some doubts about it being an actually viable weapon as opposed to a stunt.

[mlangsdorf]

The two traditional problems with man-portable miniguns are ammunition weight and recoil force.

A 5.56mm minigun consumes around 4-5 lbs of ammunition per second, so even if the gun is somehow light enough to be man portable, carrying useful amounts of ammunition is a problem.

The recoil from a single 5.56mm round is manageable, but 60-100 per second produces enough force that its hard to remain standing (I recall it's something like 70 lbs of force, coming at right angles to the way the human body is used to withstanding force).

Finally, there's a question of why make a man-portable mini gun. SAWs and GPMGs provide adequate amounts of fire-power, preferably fired from a bipod or light tripod, but can be briefly fired from the shoulder if necessary. Actual miniguns work well from vehicles that need to saturate area while on the move, such as helicopters. There's no good role for a man-portable mini gun that justifies solving the engineering issues.

Even if you assume some kind of super-human carrying the gun - either a time-traveling assassination robot or someone in powered armor - there aren't a lot of instances where a 5.56mm minigun is preferable to a 0.50 BMG. RoF isn't usually better than range and penetration.

[ehrbar]

Originally Posted by Bathawk

Hello, I have another "Gun Question"

DO man-portable mini-guns exist?

So, High-Tech actually talks about this and gives stats for a "man-pack" configuration in the entry for the GE M134 (pp.135-136), specifically citing Predator and Terminator 2.

The XM214 6Pak, which was basically the M134 scaled down from 7.62 to 5.56, is not covered in 4e High-Tech, but was in 3e High-Tech (p.120).

My 4e stats for the XM214 gun are actually included in this PDF on page 6 (light flying carpets are a use-case that wasn't available in the real world that the gun fits), but the assumption there is that it's tripod-mounted; presumably it would have a similar transformation as the M134 if converted to man-pack.

[Fred Brackin]

Originally Posted by ehrbar

So, High-Tech actually talks about this and gives stats for a "man-pack" configuration in the entry for the GE M134 (pp.135-136), specifically citing Predator and Terminator 2.

.

Hans Christian Vortisch was fairly emphatic that there is only one full scale man-pportable prop minigun in Hollywood and the same gun/prop appeared in both Predator and Terminator II and he knew who owned it and what it cost to rent it for filming. I've learned to stop arguing with Hans about his research.

In the last paragraph of the GE M134 text on p.136 you'll see most of this based either on what Hans knew about the prop or what you'd have to do to make it semi-practical. You might shave a few lbs off the weight by starting with the Dillon version with titanium components in the paragraph above.

Also, Hans was somewhat dismissive of the actual existence of the "XM214" from the previous version of HT but going downward from 7.62mm to 5.56mm would reduce the weight and recoil to some degree.

If you look in Seals in Vietnam you will find a backpack hold 400 rounds of 5.56mm that fed a single-barrelled SAW (the so-called "Death Machine" configuration)and I read of such a thing being reinvented by US soldiers in the recent unpleasantness in .......probably Iraq but it could have been Afghanistan.

In 3e t wouldn't have been that hard to put a hundred rounds into a man-sized target and it might have seemed Kewl even if it wasn't practical. In 4e it's not happening and all you get would be a slightly higher bonus to hit and a couipel more rounds.

[sir_pudding]

Originally Posted by Fred Brackin

In 3e t wouldn't have been that hard to put a hundred rounds into a man-sized target and it might have seemed Kewl even if it wasn't practical. In 4e it's not happening and all you get would be a slightly higher bonus to hit and a couipel more rounds.

What you do get is a lot of suppression, which is why anybody does the backpack belt feeds.

[Fred Brackin]

Originally Posted by sir_pudding

What you do get is a lot of suppression, which is why anybody does the backpack belt feeds.

You shouldn't be getting any more suppression out a man-portable mingun than you'd get out of a single-barreled SAW. You'd get more time suppressing out of the lower ROF weapon.

It wasn't the backpack belt feeds I was calling impractical.

[sir_pudding]

Originally Posted by Fred Brackin

You shouldn't be getting any more suppression out a man-portable mingun than you'd get out of a single-barreled SAW. You'd get more time suppressing out of the lower ROF weapon.

It wasn't the backpack belt feeds I was calling impractical.

Ah, I thought you were talking about the SAW.

[Pursuivant]

Originally Posted by mlangsdorf

The two traditional problems with man-portable miniguns are ammunition weight and recoil force.

Which makes me wonder whether the weapon harness described in Ultra-Tech might have real world applications, if only as a prop.

The only way a man-portable mini-gun in military caliber would be useful is if you reduced the rate of fire to near normal infantry MG rates of fire and reduced the number of barrels to 3 or 4. Since machine gunners carry spare barrels, no reason not to mount them on the gun to begin with. Rotating barrels might help keep them cool, which would aid useful lifespan.

The drawbacks would be the need to carry a battery back and the extra maintenance required, which aren't trivial considerations if you're supplying an army and if the weapons are expected to perform reliably in terrible conditions. The options of switching from minigun to single barrel fire and allowing the gunner to manually advance the barrels in case the battery dies would be helpful.

Miniguns are mainly useful if you're trying to put a massive number of bullets into a relatively small area in a hurry, which is why they're used as aircraft and ground attack weapons. They're also good as short-ranged anti-aircraft weapons, but MANPADs do the job better.

The one emerging role where I could see a man-portable minigun being used is as a drone defense. It's not economical to shoot MANPADS missiles at the sort of small suicide, attack and recon drones being used in Syria and Ukraine and conventional infantry MGs might struggle in the AA role. The gun could switch computer-aided chaingun AA mode for squad anti-drone defense to single-barrel operation when engaging ground targets.

[Fred Brackin]

Originally Posted by Pursuivant

The options of switching from minigun to single barrel fire and allowing the gunner to manually advance the barrels in case the battery dies would be helpful.
.

You would have to design an entirely new mechanism and I fear it might have impractical complexity. With gatlings (and chainguns which are a different thing) the same electric motor that turns the barrel assembly advances the ammo into the barrels.

Stopping the electric operation and switching to single barrel would require putting in a separate recoil or gas action mechanism. You've got an extremely complicated combination weapon then. Even adding a manual crank to operate the gatling mechanism would add weight and probably make the weapon even more unwieldy.

Use that weight to carry an extra battery pack. It's not like your ammo supply is going to last longer than your batteries anyway.