The Pima Air and Space Museum has an A-10 Warthog on display. That’s an impressive aircraft with impressive features. The most impressive, I think, is the Warthog’s GAU-8/A 30mm Gatling gun. “GAU” is the military abbreviation for modern Gatlings. It stands for Gun, Automatic, Utility, and it’s pronounced “Gow.”
Viewed from the front, the A-10’s Gatling gun seems like it is offset from the aircraft center line. The reason is only one barrel fires at a time as the barrel cluster rotates, and it does so when it is on the aircraft centerline. When firing at the gun’s maximum rate (4,000 shots per minute), the recoil equals the A-10’s 18,000-pound max thrust. If the firing barrel was not on the aircraft centerline, the gun would steer the aircraft when firing.
The Fairchild A-10 Warthog.
The photo below shows the A-10’s Gatling muzzle clamp, which is the device that holds the gun’s seven barrels together at the forward end. The barrels are welded shut on this display aircraft to prevent a bad guy from stealing and using the gun.
The A-10 muzzle clamp. The rifling in each barrel is visible here. 30mm is 4.6mm larger than 1 inch.
The muzzle clamp’s center bolt secures the muzzle clamp to the barrel cluster. Maintenance folks never stand in front of the gun when removing the muzzle clamp. Applying torque to the muzzle clamp bolt might rotate the barrel cluster, doing so could bring the firing barrel into position, and if the gun is loaded, it might fire. In the old days of the Civil War era Gatling guns, it was not uncommon for a soldier to inadvertently fire a round when attempting to remove the muzzle clamp.
Here’s the A-10’s GAU-8/A Gatling removed from the aircraft (another Pima Air and Space Museum display item). It’s about the same length as a Volkswagen Beetle.
The A-10 GAU-8/A Gatling gun. These guns were manufactured by General Electric in Burlington, Vermont.
This next photo shows the gun’s bolts (there’s one for each barrel). It also shows the elliptical cam path in the gun’s rear housing. The elliptical cam path that drives the bolts back and forth as the barrel cluster rotates. That was Dr. Gatling’s original idea. All Gatling guns use this concept, from the first Gatling gun in 1862 to the modern Gatlings.
The Gating gun’s rear housing assembly.
If you are interested in the Gatling gun, its history, and its current applications, you might want to pick up a copy of The Gatling Gun.
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I am a fan of both the No. 1 and the No. 3 Ruger single shot rifles. The No. 1 is the more elegant rifle with a fancier lever, a pistol grip stock, checkering, a rubber shoulder pad, a slick quarter rib, fancier walnut, and more. The No.3 was the economy version without checkering, plain walnut, an aluminum (and later plastic) shoulder pad, and a no frills look. When I started collecting these rifles in 1976, the No. 1 was chambered in contemporary cartridges and priced at $265. The No. 3 came in classic chamberings; in 1976 that included .22 Hornet, .30-40 Krag, and .45-70. Ruger listed the No. 3 at $165, and you could buy them all day long for $139. Which I did. In 1976, I bought No. 3 rifles in all three chamberings. All had the “Made in the 200th Year of American Liberty” inscription.
Take a look at the finish on this Ruger No. 3. It’s better than how they came from the factory.
I was younger and dumber in those days, and I stupidly sold all three rifles within a year of purchasing them. The Hornet went to Army buddy Jim, the .45-70 went to another Army buddy also named Jim, and the .30-40 was traded for something else I can’t remember. If you’re reading this blog, you realize the phrase “stupidly sold” is redundant. We have all sold guns we wish we kept.
Ruger has to have one of the best fonts ever for chambering designation.
I wanted to undo the wrong I did, and about 15 years ago I started a search to replace my No. 3 rifles. The .45-70 was the easiest to find and the .22 Hornet followed shortly thereafter. The prices had gone up (used, they were going for about $650-$700 back then). The .30-40 Krag was tougher to find. I’m assuming it was because Ruger made fewer of them. Then I spotted something I had to have: An unfired .30-40 No. 3 advertised on Gunbroker, and it had significantly nicer wood then No. 3 rifles typically have. I had to own it and I paid top dollar. When I called the shop, I used my American Express card instead of a certified check because I was eager to get it. I had to pay a 4% premium, but that turned out to be a good thing (more on that in a second).
Unusually highly-figured walnut on a No. 3 Ruger.
The shop that sold it to me did something stupid. They shipped the rifle in the original box with no additional padding and they didn’t insure it. You could get away with shipping a No. 1 Ruger in the original box, as they were stout and contained big pieces of foam padding. The No. 3 had a flimsy cardboard box in keeping with the No. 3’s lower price. You can guess where this story is going.
A view of the No. 3’s port side at the West End Gun Club.
Yep, the rifle arrived with the stock broken at the wrist. Wow. The wood was as beautiful as it looked in the Gurnbroker.com ad, but it was busted. I had a brand new, unfired 200th year No. 3 in .30-40 Krag with nice wood and its collector value was ruined. Like the box, I was crushed.
I called the shop owner, who turned out to be a real prick. “It’s your problem, and it’s between you and the US Post Office,” he told me. “You didn’t tell me to insure it, so I didn’t. Once it leaves here, it’s yours.” I told him I was going to have the stock repaired and I offered to split the cost with him, but he kept repeating his mantra: Once it leaves here, it’s yours.
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I told this sad story the next day during our usual geezer gathering at Brown’s BMW in Pomona, and good buddy Dave asked if the gun shop had asked me about insurance. “Nope, he never asked and I didn’t mention having it insured. I guess I just assumed it would be.” Dave explained that I was right to make that assumption, so I called the shop owner again, I explained to him I had learned about insurance responsibilities, and I again offered to split the repair cost. He said no again.
Then I remembered I had used my credit card. I called American Express, I explained the situation, and I told them it would cost about $275 to have the stock repaired and refinished. Not a problem, the guy on the other end of the line said, and just like that, he took $275 off the charge and said that the shop owner had 30 days to appeal. He didn’t, and that was that.
I sent the rifle off and when it came back I was both pleased and disappointed. I had asked the place I use for such work to match the original Ruger finish, but they did not. Instead, it was a much deeper and more glorious oil finish. It was nicer than the original finish, but it wasn’t original. That was good news and bad news. I had planned to keep the gun in its unfired condition, but now that it was busted, repaired, and refinished, it would be a shooter (that was the good news).
You can just barely see where the crack was in the stock wrist, but that’s because I used flash for this photo. In normal light, you really can’t see it.
I didn’t shoot the No. 3 immediately. This all happened 15 years ago before I retired and before COVID hit. I recently decided I needed to shoot the .30-40, so I ordered unprimed brass and Lee’s Ultimate four die set. Both were initially unavailable, but they came in and I was in business. I already had large rifle primers, a stash of what has to be one of the best powders ever for cast bullets (SR 4759), and a bunch of 173-grain gas checked bullets.
.30-40 Krag ammo in new brass, loaded by yours truly.Ready for the range.
I seated the cast bullets to the crimping groove and used the Lee factory crimp die, and the cartridges looked great. I tried a number of different SR 4759 powder charge levels in the Lyman cast bullet manual. When I fired on the 50-yard line at the West End Gun Club using the rifle’s open sights, I found that 20.0 grains of SR 4759 is my accuracy load.
I held at 6:00, and the rounds shot very close to point of aim at 50 yards. The target was mounted on its side, as you see it here.Very modest bore leading in the No. 3. That SR 4759 load with the 173-grain bullet is accurate even with the Ruger’s factory iron sights.
The .30-40 Krag is an interesting cartridge. It was the US Army’s standard chambering after they phased out the .45-70 Springfield. The new rifle was the 1892 Krag-Jorgensen rifle made at the Springfield Arsenal. It was the first military cartridge designed for smokeless (as opposed to black) powder, and it originally fired a 230-grain jacketed bullet. The .30-40 is a rimmed cartridge that looks a lot like the 7.62x54R Russian cartridge (which came out just one year earlier). The ballistics of both are fairly close to the .308 Winchester (which is the 7.62 NATO round we currently use).
.45-70, .30-40 Krag, 7.62x54R Russian, .308 Winchester (7.62 NATO), .30 06, and .300 Weatherby cartridges. The .300 Weatherby is the fiercest recoiling cartridge in the group when loaded with jacketed bullets at factory velocities (the cartridge shown here is loaded with a cast bullet). With the exception of the .300 Weatherby, Gatling guns have been chambered in each of these cartridges. Modern mini-guns are electrically-powered Gatlings chambered in 7.62 NATO (.308 Winchester).
After our experiences in the Spanish-American War, our government load plant created and issued a hotter version of the .30-40 Krag in an attempt to match the speed and ballistics of the Spanish 7mm Mauser round, but the Krag rifles started cracking bolts. All the .30-40 Krag ammo was recalled and reconfigured with the original, lower pressure load. The .30-40 Krag was also used in the Gatling gun. You can read about that here:
The .30-40 Krag only lasted about a decade in US government service. It was replaced with the .30-03 in 1903 (which was soon replaced with the .30-06, which became one of the most popular hunting cartridges ever). The history of this fine old cartridge is interesting; shooting it with cast bullets in a sleek Ruger No. 3 is good old fun. I might never have known that if the stock had not broken.
A scan of a photo of a photo. I handled the original while researching the Gatling gun in the Colt archives at the Connecticut State Library and Museum in Hartford.
Yeah, I know…a Gatling gun is not a machine gun. It was a hand-cranked weapon back in the day, but it’s still a fascinating a bit of machinery and this Civil War weapon concept is the principle behind modern high-rate-of-fire systems on combat aircraft, helicopters, naval vessels, and more. I was so captivated by the Gatling design and how it extended from the Civil War to modern gun systems that I wrote a book about it (The Gatling Gun). You may have already known that.
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The Gatling gun and its transition from the 1860s to today’s modern combat applications is fascinating. To get that full story, you might want to pick up a copy of The Gatling Gun.
So how did it come to be that modern high-rate-of-fire gun systems use the Gatling principle?
Here’s the deal: Around the end of World War II, jet aircraft entered service, and the old .50-caliber M2 Browning simply didn’t fire fast enough. With the new jets, aircraft closing speeds in a dogfight might exceed 1000 mph (two jets coming at each other over 500 mph), and what was needed was a shot pattern rather than a steady stream of bullets. In searching for higher firing rates, the Army discovered that Dr. Gatling and the U.S. Navy had both experimented with Gatling guns powered by electric motors, and way back in 1898 they attained firing rates over 1000 shots per minute. In 1898, a firing rate that high was a solution looking for a problem that did not yet exist. So, the concept was shelved for the next half century. But after World War II, it was the answer to the Army Air Corps’ jet fighter gunnery dilemma. The U.S. military dusted off the concept of an electrically-driven Gatling, gave a contract to General Electric, and the modern Vulcan was born.
Like I said earlier, the Gatling gun and its variants are used on many different combat systems. One of the earlier ones was immortalized by Puff, the Magic Dragon, in The Green Berets.The Green Berets is one of my all time favorite movies and the scene I’m describing shows up at around 1:20:
The first Vietnam-era gunship used old World War II C-47s (that’s what you see in the video above). Then the Air Force went to the C-130, a much larger aircraft, because it could carry more cannon. Then, because they couldn’t get C-130s fast enough, they turned to old C-119s. When the Air Force did a range firing demo to convince the folks who needed convincing at Eglin AFB, the gunship Gatlings fired continuously until they had no more ammo, and I’m told it was so impressive the project managers secured an immediate okay to proceed. The bigwigs viewing the demo firing thought the sustained burst was all part of the plan; what they didn’t know is the control system malfunctioned and the aircrew couldn’t turn the Gatlings off. Hey, sometimes things happen for a reason.
I know a fascination with Gatlings is unusual, and you might wonder how it came to be. It goes like this: When I was in the Army, my first assignment was to a Vulcan unit in Korea. To ready me for that, I had orders to the US Army Air Defense School’s Vulcan course in Fort Bliss, Texas. Vulcans were the Army’s 20mm anti-aircraft guns, and on the first day of class, the sergeant explained to us that the Vulcan gun system was based on the old Gatlings. Whaddaya know, I thought. The Gatling gun.
Then things got better. After a few weeks of classroom instruction, we went to Dona Ana Range in New Mexico to fire the Vulcan. I thought the Vulcan would sound like a machine gun…you know, ratatat-tat and all that. Nope. Not even close. When I first heard a Vulcan fire I was shocked. If you’ve ever been to a drag race and heard a AA fuelie, that’s exactly what a Vulcan sounds like. I heard one short BAAAAAARRRKKK as the first Vulcan fired a 100-round burst at 3,000 shots per minute. Jiminy! The effect was electrifying. We were a bunch of kids yammering away, and then the Vulcan spoke. Everyone fell silent. We were in awe.
At the Dona Ana range, the effect was even more dramatic…there was the soul-searing bark of the actual firing, and then an echo as the Vulcan’s report bounced off the distant Dona Ana mountains. Then another as the next gun fired, and another echo. And another. Cool doesn’t begin to describe it.
A Vulcan firing at night. Think that shot pattern is impressive? Hey, you’re only seeing every 7th round (the combat mix was one tracer every 7 rounds). This is a US Army photo included in The Gatling Gun (along with many others).
After I left the Army, my next job was on the F-16 Air Combat Fighter, and it used the same 20mm Gatling as did the Vulcan. After that it was General Dynamics in Pomona, where I worked on the Phalanx (a 20mm shipborne Vulcan). Then it was on to Aerojet, where we made 30mm ammo for the A-10 Warthog’s GAU-8/A Gatling. It seemed that every job I had was somehow tied to a Gatling gun variant, and that was fine by me. I loved working with these systems.
And there you have it. If you’d like to more about the different systems using Gatlings today and the early history of the Gatling gun, you can purchase The Gatling Gunhere.
