By: Friedrich Seiltgen

Gunpowder readers know my affection for the Gatling Gun. As an F-4 Phantom weapons loader, I filled a few 20mm & 30mm gun pod units.

The 20mm Vulcan has a little brother with the XM134 Minigun in caliber .308, and it’s been a military staple since Vietnam. Throughout the years, Dillon Aero of Scottsdale, Arizona has been making steady improvements to the original design to the point that many think Dillon invented the Minigun! Not content with the success of their updated minigun, Dillon Aero has been working on something new.

Dillon introduced their newest design recently at the 2020 SHOT Show: the 503D Tri-Barrel gatling gun in caliber 50BMG! The 503D looks very futuristic, and with its barrel shroud looking like a nacelle from an SR-71 Blackbird, rest assured the 503D will be making its debut on the big screen soon.

Dillon Aero Press Release:
Dillon Aero is developing a new .50 caliber Gatling gun, known as the 503D. This gun system will be lighter, faster, and smarter than existing .50cal machine guns. It will fire 1,500 shots per minute with the ability to adjust the precise firing rate based on platform integration to optimize mission performance. The gun is designed to have integrated immunity to internal component damage from ammunition feed jams. The current gun weighs 84 lbs. (38 kg).

The technology used in the gun system provides the operator unlimited information on how the weapon operates, and possible failures that could be prevented with current maintenance data, and increased safety.

Caliber: 50 BMG (12.7×99mm NATO)
Rate of Fire: 1,500 rounds per minute
Weight: 84 lbs. (38 kg)
Designed for component damage immunity
Lighter, faster, smarter

Caliber: 50BMG (12.7×99mm NATO)
Rate of Fire: 800 rounds per minute
Weight: 84 lbs. gun only, with tripod 128 lbs.

The 503D will be marketed for sea, air, and land use. The photo from Dillon Aero shows the unit with mounting lugs to attach it to an airborne weapons pylon. It will be vehicle mounted also. I’m looking forward to this weapon becoming fully operational soon, and with Dillon Aero behind it, it shouldn’t take long.
P.S. Gunpowder fans! Dillon Aero also brought out their experimental Minigun in the new .338 Norma Magnum caliber. At first glance, it looks like their standard XM-134 minigun in caliber 7.62X51. Now start counting barrels! The new minigun features five barrels instead of six!

In a previous article, GPM profiled the new SIG MG338 Machine Gun being procured for SOCOM. The military is beginning to transition to the .338 Norma Magnum Caliber, as it has better penetration at longer ranges. Naturally, Dillon figured they could use a minigun in the new caliber. The .338 Norma Mag goes well with Dillon’s line of minigun gun pods for use on helicopters and light aircraft. The hotter cartridge will allow gun runs from longer ranges and also provide better accuracy. No word on its rate of fire, but I’m sure it will be in the 3,000 rpm range!

That’s all for now, and as always, Be Safe Folks!

Friedrich Seiltgen is a retired Master Police Officer with 20 years of service with the Orlando Police Department. He is currently a part-time policer officer with the Starke, Florida Police Department. He conducts training in Lone Wolf Terrorism, Firearms, First Aid, Active Shooter Response, and Law Enforcement Vehicle Operations in Florida. His writing has appeared in The Counter Terrorist Magazine, Homeland Security Today, and The Journal of Counterterrorism & Homeland Security International. Contact him at [email protected].

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