Category Archives: Weapons Technology

The Brief Moment of the Revolving Carbine

This past weekend, the 200th anniversary of Samuel Colt’s birth (19 July 1814) was celebrated by a bunch of Connecticut arts types, in nearly gun-free Connecticut fashion. If any of these professional irony enjoyers noted the irony, they didn’t say anything about it. But that’s got us looking at some of Sam’s accomplishments, and that brought us around to one of Colt’s least successful products: revolving carbines.

In the middle of the 19th Century, the best and greatest means of rapid fire was the revolving pistol. It seems like a natural idea to extend that to a revolving rifle or carbine; and this, Sam Colt did, as early as 1839. This brief (minute and a half!) video shows an extremely rare 1839 .52 caliber Colt that actually was one of a mere 360 acquired by the US Navy, and is now in the possession of the National Firearms Museum:

This Paterson Colt carbine was made from 1838 until 1841, and apart from the Naval guns, which may have been used by the Marines at the Siege of Veracruz in the Mexican War, too late to do that version of Colt’s company any good: the Paterson firm went bankrupt, and Colt had to start over. He retained his patents, so that whatever happened to his companies, the crown jewels were safe with him and his family. (This was prescient of him, for he was to die young).

The Mexican War not only gave the Marines a new direction (the landing at Veracruz was the first of what would become a standing Leatherneck specialty, amphibious landings on defended shores), but it resuscitated Colt, due to a military order for 1,000 revolvers, which were delivered before war’s end and are known as the Colt Walker revolvers.

The refreshed Colt Patent Fire Arms Manufacturing Company had a new, improved carbine by 1855, incorporating all of Colt’s new patents, and was producing it, and the more popular revolving pistols, in a new Armory building that was the marvel of Hartford, in a planned industrial community on an area of reclaimed land (note the berms or dikes in the image below). The area that encompassed all of the Colt factory, its workers’ housing, and Colt’s own grande manse was officially called the “South Meadow Improvements” but came to be known as Coltsville.

colt-armory-color-retouch-H

 

The carbine had two problems, both insurmountable from the military point of view. It was very expensive (the 1855 carbines cost the military $44 each, $1,189 in 2014 dollars), and, while it was safe if loaded and fired with care, a flash-over that was not usually that big a disaster with a revolving pistol had the potential for shredding a rifleman’s support hand. If there is a right way and a wrong way to load a weapon, no organization made of humans will ever be able to train 100% of its people to do it right 100% of the time.

When the Armory burned down in 1864, a $2 million plus ($54M plus 2014) loss of inventory, machinery and jigs to Colt, of which about $1.4 million ($38M) was excess to insurance carried, the remaining plant was used to manufacture pistols exclusively; the demand for Colt revolvers was inelastic, and repeating cartridge firearms on the horizon rendered the revolving rifle or carbine obsolete. The total production of the Colt carbines was very low; the 1855 was scarcely more produced than the 1839 version.

After the Civil War, Remington produced a version of its revolver as a carbine, also finding it disappointing in sales, although not as much so as the Colt version had been.

Since the 1960s, several versions of replica Colt and Remington carbines have been made. These are more frequently collected, from what we’ve seen, than fired; used ones usually have far more handling marks than they do indicia of firing.

The great Cap and Ball Channel from Hungary has posted three great videos on two carbines, an original Colt and an Uberti copy of a Remington.

Part 1, about the Colt (~6 minutes). The music is pretty awful, especially when it isn’t ducked under the voice, but the analysis of the unique mechanics of the gun makes it well worthwhile:

Some of the unique features of this .44 caliber Colt 1855 include progressive depth rifling, and a cylinder that is rotated by a ratchet on the rear end of the cylinder pin. This gun may be a bit off the military norm, as it appears to have been a sporting gun originally sold in Europe (it bears English proofs).

Part 2, about the Uberti clone of the Remington (~3 minutes):

Part 3, both are taken to the range (yes, even the very valuable original Colt) and shot for accuracy. If you’re only going to watch one video, this is the one. It also shows loading with loose powder and conical bullets, but also with period-style paper cartridges, which is how the real Billy Yanks and Johnny Rebs would have done it. (Not to mention everyone else who went to war with percussion, like the British, French and Russians in the Crimean War, all manner of 19th Century naval riflemen, and the British in the Afghan Wars). This one’s about six and a half minutes.

The Capandball.eu site and associated YouTube channel is a real find, but we didn’t want to wait for a TW3 to show it to you.  If we have any beef with the chance to watch the two percussion revolver carbines on the range, it’s that he didn’t quantify their accuracy. But they look like fun, and one’s a sample of a moment in time that will never be repeated — the other shows us that the artifacts can be repeated, even if the times can’t be.

These firearms were an interesting evolutionary dead end (sure, there are cartridge versions, even a Taurus Judge carbine, but these are dead ends, too — curiosities). They came about because they were the logical progression combining proven examples of a known technology (the percussion rifle and the percussion revolver) into a hybrid that seemed like it had a bright future. (After all, if you were a cavalryman, or a Pony Express rider, another customer for the Colt ’55, wouldn’t you rather have six shots before facing the difficulty of reloading on horseback than one?). But unbeknownst to Sam Colt, and to his designer and right-hand-man Root, a technological disruption was on its way: new cartridge repeaters were coming that would eliminate all the disadvantages of the revolver carbine.

Root kept Colt relevant with cartridge revolvers, and even before the Colt family sold the company in 1901 new managers were embracing the novelty of the automatic pistol. Like Apple 100 years later, the company had a knack for grabbing hold of a technology that was about to take off in time, before its customers even knew that that was what they would want. But you don’t get to that kind of position without tripping down a few blind alleys. And thus, we have the Colt Revolver Carbine and its clones and imitators, a novelty for collectors and curiosity seekers.

Three Contenders for the Belt (belt of 5.56 in M27 links, that is)

Here’s Jeff “Bigshooterist” Zimba on belt-fed ARs. You know you’re in for detailed, accurate information and a lot of enthusiasm when Jeff steps up to the camera. You also will get better than the usual YouTube signal-to-noise and filler-to-fact ratios with Jeff on the job:

Jeff’s just slightly mistaken about the original belt-fed, backpack AR-10: it was a pre-Colt Armalite project, and wasn’t picked up by Colt. The video he refers to was a Fairchild promotional video, and here is a version of it. We apologize for the poor quality. The belt-fed version shows up (initially, in Gene Stoner’s hands!) at about 12:30. The weapon’s belt feed does resemble the later Ciener AR-15 conversion, but uses a nondisintegrating belt feed.

Returning to Jeff Zimba’s presentation, his technical points on the Ciener conversion, which is mechanically similar to at least one of the Armalite prototypes, are accurate and informative. It had a number of features that made it rather fiddly, dependent on some design oddities, and generally flawed. Nonetheless, it worked; it could just do with some improvements. Jonathan A. Ciener has been many things in the firearms community, including an innovator; but nobody ever accused him of being keenly attuned to customer sentiment, and the modifications and improvements were left as inspirations to others.

The Valkyrie BSR Mod 1 (BSR = “Belt-fed Semi-automatic Rifle”) is fundamentally an improved Ciener mechanism. The improvements are significant in convenience and function, and Jeff explains them in great detail.

The ARES Shrike is a completely different mechanism that uses a MG-42-like feed mechanism. This gives it some significant advantages over the others. It uses standard links, feeds like every standard belt-fed out there for the last 60-plus years, and can be moved to any standard lower with only one reversible modification (unlike the surgery the Ciener and Valkyrie belts require). Unlike the Ciener and Valkyrie, it alters the AR system to be gas-tappet operated. The operator interfaces with the ARES by a folding, nonreciprocating charging handle on the left side, and an extended bolt release that is the only part that must be changed on a standard AR lower.  The ARES also has quick-change barrels, a necessity for high sustained rates of fire.

All of the weapons Jeff demonstrates also can fire from magazines. Ares Defense does make a version of their belt-fed for military and LE customers that lacks magazine feed, the AMG-1 (the version with both belt and mag feed is the AMG-2. There’s also an AMG version with the quick change barrel and tappet gas system, but mag-fed only).

Jeff doesn’t say, but the Valkyrie and ARES belt-feds are still available. Valkyrie Armament also has the modified M27 links, and belt start and stop tabs that are required by its rifle (they should work with a Ciener conversion, but we’d call Valkyrie to check, before ordering).

Hat tip, the Gun Wire.

SMG History on the Block: German MP18-1

Here’s a true piece of submachine gun history: a German MP.18–1 submachine gun, a very early, first-generation, Bergmann-built Hugo Schmeisser design.

MP18-1 left

Schmeisser was the son of designer Louis Schmeisser, who also worked at Bergmann and created the early Bergmann auto pistols. Hugo is one of the true greats of 20th Century weapons design in his own right, but, oddly enough, he is credited more in the popular mind for a gun he didn’t design, the MP 40, than the many guns he did, including the revolutionary MP.18. We’ll explain below how that probably came to pass.

Discounting the curious and tactically unsound Villar–Perosa, the first real submachine gun was the MP.18. (Maxim produced a model only in the late 19th Centuryl he didn’t follow up). It was blowback-operated and fired in full-automatic only (at a rather low rate of fire, thanks to heavy reciprocating parts). The weakness of the MP18, apart from its weight and cost of manufacture, was its magazine feed: it used the 32 round snail drum of the Artillery Luger. (A snail “drum” is not a true drum, exactly, but a box magazine oriented in a spiral to save space. It’s very tricky to design). The snail drum was awkward, hard to load, heavy, and made the MP18 unwieldy, but the gun still proved its worth in the hands of German Storm Troops in the last year of the Great War.

MP18-1 right

After the war, Schmeisser patented an original design for a 20-round double-column single-feed magazine and a suitable magazine housing (the patent was not filed in the USA until 1931, possibly due to the terms of the Treaty of Versailles). This gun is one of the 20-round versions.

Schmeisser US1833862-2 According to Small Arms of the World by Smith and Ezell, these guns were not new production, but were modified by Haenel, and (several other sources suggest that Bergmann lost its production facilities at war’s end, and continued only as a design shop). Some online sources assert that during the war, Schmeisser’s double-column mag had been rejected by the Army in favor of the snail drum, officially the “Trommelmagazin 08″ or TM08, that was already in production for the Artillery pistol. We haven’t seen a definitive source that says that Schmeisser’s stick mag was ready for prime time in 1918.

This gun on offer is one of those postwar MP.18-1s with the 20-round box mag.  Its condition is amazing for a nearly-century-old weapon an ocean away from its home:

MP18-1 right2

This is a excellent German MP18.1 that I have had for a long time. It is in beautiful original condition as you can see by the pictures. It is all matching except for the bolt. The bore is excellent and shiny. It has all the original finish and is NOT re-blued. The magazine housing is marked S.B.848 and the stock is marked “1920″ so I’m sure that it was used in the Weimar as a Police Weapon.

MP18-1 b

The “1920″ marking was applied to all Reichswehr (the Weimar Republic’s 100,000-man rump army) weapons when a postwar law banned automatic weapons for the general public. (This early German gun control law was to lead to greater things, but let’s not digress).

It is on a form 3 and is fully transferable on a form 4, though it can NOT be transferred on a C&R. If you have any question or need more pictures please ask.

via German MP18 1 9mm MP18-1 : Machine Guns at GunBroker.com.

The MP.18 was redesigned by Hugo Schmeisser into a slightly improved version, the MP.28, which had a selector switch. It continued in production, spawning many variants. The Schmeisser designs went on to be extremely influential, as well as to serve in many other wars, including the Spanish Civil War, the Sino-Japanese Wars leading up to World War II (including in Chinese-copy versions), and of course in World War II, where it was often found in the hands of the SS. It also inspired the British Lanchester, a fairly direct copy of the MP.28 which actually could use MP 18 and 28 box magazines, although the Lanchester also had 32 and 50 round magazines of its own. This makes the MP 18 not only the progenitor of all submachineguns, but also the granddaddy of the Sten. The Japanese Type 100 was also a modified copy of the MP.28, a weapon the Japanese had encountered in Chinese hands. The Finnish Suomi and Russian PPD also were inspired to one extent or another by the German design, and the.

Schmeisser’s box magazine design was patented, as shown above, and was widely used in subsequent guns. It’s generally accepted that the misnomer “Schmeisser” for the MP40 came about because many MP38 and MP40 magazines were marked with “Schmeisser D.R.P.” (Deutsches Reich Patent) in recognition of this patent.

The gun is extremely durable. The receiver is machined from a thick tube, unlike the thin tubes common in Second World War submachine guns. The bolt likewise is machined from a single block of steel. The weapon fires from an open bolt, automatic only, although experience makes single shots possible. The original WWI versions had no manual safety. This one has a bolt notch safety. (All open-bolt SMGs are only safe with a mag out, period, unless the safety locks the bolt forward on an empty chamber. A safety like this just instills false confidence).

MP18-1 right3

Mullin notes that, other things being equal, a full-stocked SMG always provides a better firing platform than a folding or sliding stock. We concur. Sliding stocks have had something of a renaissance due to body armor, but for the recreational shooter an early subgun like an MP.18 (or a Thompson for that matter) is a joy to shoot.

MP18-1 broken open

While the operating system of the gun was very simple, the internals were not. The bolt was driven by a telescoping spring guide/firing pin mechanism clearly antecedent to that of the later Vollmer designs that would culminate in the MP40. What killed the MP.18 and its successors in the end was the difficulty and expense of machining its solid steel parts. Second-generation submachine guns would have stamped, die-cast, and other parts taking advantage of improvements in 20th Century automotive mass-production industrial processes.

MP18-1 stripped

We’ve used more of the pictures than we usually do in these auction reports, because this is such a gorgeous, unmolested original gun. If we hadn’t just taken a huge income hit (thank you, ISIL), we’d be on this like a lawyer on an ambulance.

Because the MP.18 isn’t as sexy as later guns, it’s unlikely to be bid up anywhere near Thompson, BAR or M16 territory, and might even sell down in the Sten price range. But this gun is a true piece of history. Its next owner will have something to be proud of, and it may turn out to be a good investment. (Personally, we don’t “invest” in anything subject to corrosion, although we’ve been known to delude ourselves that we did that).

After this, you might want more information on this rare and historic firearm. There’s a minimal write-up in most editions of Small Arms of the World. In the 11th Edition it begins on p. 338. (The book, not the unrelated Small Arms of the World website. There’s probably a good writeup on the website, too, but we’ve been locked out by login problems over the last few weeks… we hope to get them resolved today. SAW’s technical staff have been very helpful). There’s a better writeup, but scarcely a thorough one, in Hobart, on pp. 116-117.

How does the MP.18 stack up today? Mullin’s verdict in The Fighting Submachine Gun: A Hands-on Evaluation was:

The M1918 feels like a good, sturdy, long-lasting weapon. It does have a few drawbacks to it (such as weight and slam-firing bolt-design defects), but once modified to a standard box design, it has all the features necessary to make an effective SMG with very few that are superfluous to the job. This is quite a compliment to those original German designers back in 1918.

Peterson (p. 151) suggests that the gun may be worth $17,000 to $22,500, depending on whether you call its condition “very good” or “excellent”; a snail-drum wartime gun would be worth only 10% more. No one has bid on this gun, at $13,500 opening bid and no reserve. What’s up with that?

Sources: 

Hobart, FWA, Pictorial History of the Sub-machine Gun

Mullin, T. The Fighting Submachine Gun: A Hands-on Evaluation.

Peterson, P. Standard Catalog of Military Firearms: The Collector’s Price and Reference Guide. 

Smith, WHB and Ezell, EC, Small Arms of the World, any edition.

A very good photo thread on the MP.18 and successors at Accurate Reloading: http://forums.accuratereloading.com/eve/forums/a/tpc/f/7811043/m/589109167/

Note that there are a couple of errors and unsupported statements in the photo thread.

 

Stealth Research — Someplace You Wouldn’t Expect

500px-Naval_Ensign_of_Japan.svgWe confess, we may have cheated with that headline. Because you might expect that high-tech Japan is a place where research on stealth technology takes place. But it’s the time that’s interesting. You probably didn’t know that stealth technology was a subject of intense research by the Empire of Japan, and they even made some progress.

Almost every great power in the world, and a surprising number of secondary powers like Hungary, independently developed radar in the World War II or immediate prewar years. Since radar by definition depends upon a radio-frequency signal, scientists and engineers understood that the signal was subject to attenuation or degradation in the real world. And so some nations undertook studies of possible radar countermeasures, including the forerunners of what we now know as stealth technology.

Japanese scientists and military officers were extremely interested in methods of defeating radar. As anyone who studies the Empire of Japan comes to expect, the Army and the Navy took dramatically different approaches, and shared no information. The army tried to develop radar-defeating coatings or paints; the Navy was more interested in developing radar absorbent materials. Once Japan surrendered, American technical intelligence officers rushed to exploit

The introduction of a report by Japanese scientist I. Murakami would not be out of place in a modern engineering textbook’s introduction to stealth:

There are two methods by which reflections of radar signals from surfaces might be considerably reduced. One, by the selection of suitable surface contours in order to minimize reflection in the direction of the radar receiver. Two, by the use of absorbing layers of suitable characteristics applied to the surface exposed to the radar waves. It is understood, of course, that a combination of these two principles would produce the best results.

Basically, it is necessary that the absorbing layer have the smallest coefficient of reflection at the frequency of the radar wave. Therefore, initial research was on the method of measuring reflection coefficients at the very high frequencies of 3000 megacycles, and was followed by development of suitable absorbing materials, both experimentally and from theoretical data.

Murakami was writing about a Navy program to develop radar-defeating technologies that was sponsored  by the 2nd Naval Technical Institute and carried out by Dr Shiba of the Tokyo Engineering Institute and two contractors: Nippon Broadcasting Company and Sumitomo Electric. Murakami came up with a list of seven characteristics of the ideal radar-absorbing material. Note that his greatest concerns were logistical:

  1. Made of plentiful raw materials (a big issue in import-dependent Japan).
  2. Adaptable to mass production
  3. Easily layered onto an existing ship
  4. Mechanically strong materials without hidden weaknesses
  5. Thin and lightweight.
  6. Resistant to seawater and easily sealed/repaired,
  7. Should work just as well on “supersonic” waves (we think he means what we called “ultrasonic.”)

This well-reasoned material is found in two Air Technical Intelligence Group briefings, which we do not have, and a report by the US Naval Technical Mission to Japan from December, 1945, which we do have. It’s only 7 pages but it provides a synoptic view of the ATIG reports, saying:

Japanese research in the field of anti-radar coverings was quite intense, and and while several research products proved to be rather successful, according to the data presented, it was difficult to use in practice. Such information as was available is included in this report, and was obtained from the Air Technical Intelligence Group, which initiated the request for interrogations, data and samples. Reference is made to ATIG Reports 4153 and #114, the latter prepared for ATIG by Dr. Wilkenson, a civilian engineer associated with that group.

The two major contributions are an anti-radar paint, the work of Major K. MANO of the Tama Technical Institute, a Japanese Army research organization, and Dr. SHIBA of the Tokyo Engineering College, and absorbing materials, in rubber, for micro-waves. This last research was conducted at the direction of the 2nd Naval Technical Institute and engineered by the Nippon Broadcasting Corporation and the Sumitomo Electric Co.

Abstracts of the reports are given for their interest value. The basic reports of ATIG should be studied for complete details.

Many people assume that Japanese technology was extremely primitive compared to that of the US, but we’ve never encountered a Pacific combat vet who thought things were all so lopsided, and this report is an example of what Japan’s technical institutions were capable of.  It can be found online as a .pdf of scanned pages, or you can grab our OCR’d verson right here: USNTMJ-200B-0278-0289 Report E-06 OCR.pdf

The report includes some information on the specific compounds and formulations used for both the Navy’s radar-absorbing materials and the Army’s radar-absorbing paint. The radar paint worked when fresh, but quickly degraded and wound up flaking off.

 

Why do rifle cartridges have necks and shoulders?

Got asked this one by a novice and was blown away by the insight of naïveté. Why do rifle cartridges often have a necked-down design, while pistol and revolver cartridges are mostly straight? (Yes, there are exceptions on both sides, but the rule applies in general).

As with so many questions in the world of firearms, the answers are rooted in history, and specifically in the history of the technology. Of course, before there were cased cartridges, there were paper and cloth cartridges used with muzzleloaders and early breechloaders. And it didn’t occur to anybody to make them in any form other than cylindrical, fitting the barrel.

Fixed, cartridge ammunition came about in the second half of the 19th century, and at first the shapes of cartridges were limited by the ability to draw the brass alloys of the time. This meant things like smooth sided, balloon head cartridges. A classic example is the .45-70 used in most versions of the Springfield trapdoor.

Even it in the early days, some cartridges were tapered. Tape or had a couple of advantages. It might help some with extraction, always an issue in those days of black powder, but more importantly it let the volume of the case be increased relative to the diameter of the bullet.

The velocity and energy you can impart to a bullet is limited by the amount of powder you have to burn, and the time the bullet is contained in the barrel atop a column of expanding, burning powder.

Over the years since 1880 or so, cartridge cases have been reshaped due to advances in metallurgy, ballistics, weapons mechanisms, and military fashion, frankly.  The initial round of black-powder-era necked cases had relatively gradual transitions, oblique shoulders and long necks compared to modern cases, that offer sharper transitions, abrupt shoulders and shorter necks. Compare, for example, a .30-40 Krag rifle case and a 5.56 NATO case to see what we mean.

The gradual transition was a consequence of the brass of the day and the limits of brass-drawing technology. By the early 1900s, brass drawing had improved (compare the .30-06 to that .30-40 Krag). It has since seen many further incremental improvements.

The more abrupt shoulder offers some ballistic improvements. Gunsmith P.O. Ackley made a career of making “improved” versions of common hunting cartridges, including such originally-military cartridges as the .30-06 and the .223 (5.56mm). The improvement came by using a sharper shoulder angle to increase case capacity. (A Gun Digest article on the Ackley Improved cartridges is available at this link). Ackley’s quest for capacity (and velocity) reached a somewhat whimsical peak with the .22 Eargesplitten Loudenboomer, a .378 Weatherby Magnum necked down to .224 with a razor sharp 40º shoulder. (His goal was to make a 5,000 FPS rifle cartridge, and he fell barely short, as the loading data shows).

Ergesplitten Loudenboomer

(A guy whose name eludes the memory later broke that record by necking down a .50 BMG to .17 caliber, for a series of ballistics experiments).

Neck length is driven by several things, apart from the mechanism of the weapon and its limits on overall length of the cartridge. Those are bullet length (a longer bullet produces a superior sectional density, and was the fashion around 1880-1910), need for powder capacity, and need to grip the bullet. To load more powder in the cartridge requires that the shoulder “crowd” the bullet a little more. Short necks are the standard these days, but longer necks give much greater flexibility to ammo designers (including handloaders) to use multiple bullet weights while maintaining a bullet with a good coefficient of drag. Ceteris paribus, longer necks also have less throat erosion than shorter ones, an empirical fact that has several compering theoretical explanations, none proven as far as we know.

The degree to which the neck needs to grip the bullet depends on the use of and recoil of the weapon. Auto weapons and heavy-recoiling weapons need to have a good grip on their bullets. Absent crimping (often done for military rounds), rule of thumb is 1 bullet diameter length of neck for autoloading and military weapons. (Mechanical actions can go to a neck that’s 70-90% of bullet diameter, for rounds in the rough .30-06 class).

There is some theory on case neck angle and length by Chris Bekker at Reloader’s Nest. Chris notes some limits to the theory, in real life. There’s some math, but it’s junior high school level trig and algebra, nothing to be afraid of.

Learning the RPG-7

Obsolete (or at least obsolescent) in Russian service, the RPG-7 continues to serve with scores and scores of armies worldwide. Every Afghan armed force, regular or irregular, since about 1980, has used this versatile and powerful weapon.

This DOD B-roll video shows Marines training members of the Afghan National Army in the loading and firing of the RPG on 24 August 2011.  This was a train-the-trainer event; the Afghans in this video were being trained as small arms assistant instructors.

The Afghans are speaking Dari, not Pushtu. They’re firing with iron sights, not the optic (the optic takes days to train. Even the iron sights have two settings, normal and low-temperature [sub 0ºC]), and they’re using OG-7V HE/Frag warheads. This is that bad boy, in promotional makeup:

og-7

The rough midpoint of the rocket (that shiny band) is where it initiates. The firing pin of the RPG-7 is located on the ventral side of the weapon; the hammer strikes it in the “up” direction and it strikes an initiating primer. Since the primer is in only one position around the 360º circumference of the booster, the round is provided with a small lug (the “indexing lug”) that fits into a notch in the muzzle (the “indexing notch”). An RPG round that is not fully indexed and seated will not fire. The fins are contained inside the booster charge, This very nice 3D render of one of the RPG files available at “Turbo Squid,” a 3D file vendor, shows you how the fins work. It doesn’t include the safety pin and removable cap, both of which need to be taken off (as you can see in the B-roll of training video).

RPG_Grenades_Collection_03.jpg696bb774-c06b-4a1e-833c-7db268e4bc16Larger

The firing sequence and performance of this round, in all but terminal effect, apes the more common PG-7 or PG-7V warhead, the twin-conical HEAT warhead. The booster charge (section III in the cutaway PG-7V image below) expels the OG-7 from the tube at 117 m/sec (384 fps) in a tenth of a second, by which time it has traveled 11 meters (~36 feet). The booster charge is routed through a de Laval nozzle or venturi that equalizes the pressure of the gases exiting the rear of the tube with the recoil from the grenade being expelled from the front — making, in an in-spec RPG, the recoil functionally zero. At the 11-meter point the rocket sustainer (II in the cutaway) fires and propels the warhead section, hitting a peak velocity of 294 m/sec (965 fps) until it hits the target, or if it finds no target or other object or surface, until 5 seconds have elapsed. At 5 seconds, the round is 900 meters (~2950 feet) from launch, and it self-destructs.

The round is stabilized by spring-out fins hinged inside Section III (the fins are shown stowed as 17). These fins are also beveled on one side of their leading edges to provide stabilizing spin in addition to the aerodynamic stability the fins supply. In addition, a small group of secondary fins (19) provides spin even during the in-tube boost.

pg-7v_of_rpg7_sect

Here is B-Roll of an interview with one of the Marines, Sgt. Christopher Samples.He explains what the training meant to achieve, and the roles of the gunner and a/gunner in an RPG crew. “It’s commonly used, but it’s commonly misused, as well. Once they learn how to effectively use it, it can be used against the enemy.”

In this interview, ammo tech Corporal Ryan McCarthy explains how the RPG works, according to his own understanding, and what he’s looking for: “Safety. Safety, safety, safety!”

And here is the finished, journalistic product, blending excerpts from the two interviews and the range fire on 24 August 11.

The RPG is a really, really outstanding weapon, and it fits in a sweet spot of direct-fire AT and AP support weaponry that’s really missing in the US infantry squad. Instead, we have more riflemen, and additional-duty weapons like the AT-4. The RPG is cheaper and reusable, and it has a range advantage over most US disposable non-guided weapons. Its effective anti-tank range is about double that of the AT-4, and the disposable AT-4 costs $1,500 a round.

History of the Weapon

The evolutionary history of the RPG is fascinating. The Soviets began by copying a weapon they’d felt the sharp end of: the German Panzerfaust. There were many versions of this disposable AT weapon available, and by war’s end the Germans were evolving this weapon in the direction of a reusable tube. It was the Panzerfaust that originated the grenade-launch boost and rocket sustainer operating system, and the weapon evolved rapidly under the pressures of mechanized warfare. Early Panzerfäuste had a mere 30 meter range, demanding bravery, or recklessness, from a rifleman under the pressure of hordes of T-34s or Shermans. And the warheads were marginal, at least on the well-protected T-34. By 1945 most of the initial weaknesses had been allayed by the intense development taking place behind the lines, and the industrial and R&D plant fell into Russian hands.

Unlike the USA, where captured German scientists and engineers came to be trusted, with many staying on as employees and seeking American citizenship, the Soviets, who suffered terribly at German hands, never trusted the Germans and held them in rigid captivity. As quickly as possible, they transitioned German projects, including rockets, guided AA missiles, and turbine engines as well as AT weapons, to Soviet design bureaux and shut the Germans out, generally releasing them back in the USSR’s occupied zone of Germany.

The Soviet engineers proved to be quick and imaginative. They continued to improve the Panzerfaust operating system. It is generally believed that a Soviet-produced version of the late-war Panzerfaust 250 was given limited issue as the Ручной Противотанковый Гранатомёт Ruchnoy Protitankovniy Granatomet or RPG-1. A Soviet-improved version was widely issued as the RPG-2 in the later 1940s, as part of the systematic re-equipment of the Soviet Army that also saw new rifles, machine guns, and soon, tanks in service.

The limits of the RPG-2 led to the larger, heavier, more solid, and tactically longer-ranged and more accurate RPG-7 in 1961, and the versatility of the RPG-7 has kept it on the world’s front lines to this day. While most of the world knows about the remarkable longevity of the Kalashnikov rifle, its AT counterpart is just as ubiquitous, and won’t be going away any time soon. (In fact, a US firm makes a modified version for Foreign Military Sales).

The RPG has come a long way from its origins as a copy of a last-ditch throwaway weapon of the Nazi empire. Indeed, it has outlived the other empire that bore it, and stands like a monument to good incremental/iterative design. Weapons themselves have no ideology; they’re just tools, and can be used for good or for ill. This one endures because the RPG-7 version is a superior design that fits a unique tactical niche.

Why the Honeycombed Nuts are a Big Deal

It dawns on us that in our announcement of the honeycombed howitzer nuts developed by New Jersey firm Imperial Tool with SLM additive manufacturing, we did not elaborate on why we think it’s a big deal.

lighter M777 howitzer nuts

Let us walk you through it by the numbers:

  1. Until now, it’s been hard to build hollow parts.
  2. Most of the loads borne by steel parts are borne by their surfaces and perimeters. This is true of loads in tension and compression alike.
  3. What that means is: most of the loads bearing on the internal metal of the part (say, a nut or bolt) are just the shear forces between the different surfaces that are bearing different loads.
  4. Therefore, the vast majority of this internal structure is superfluous. An optimum shear web would not be solid and fill 100% of the space between, say, tensive surfaces and compressive surfaces (that is why buildings are built with I-beams rather than square solid beams)
  5. The internal solidity of, inter alia, a nut, only exists because manufacturing processes have always subtracted material from a solid (and, to a lesser extent, engineering analyses have been little developed for hollow and honeycombed parts).

So additive lets us save weight — in the case of the nuts, honeycombing the interior rather than making it solid saved 50% of the net weight of the part — and lets us save material.

The advantages of weight savings should be obvious. If you can reduce weight for the same strength, almost any application benefits. There’s also the flip side of weight savings: you can make a stronger part within the envelope of the original weight budget.

If your part is a common aluminum or steel alloy, material saving probably doesn’t offset some of the disadvantages of using additive: given present technologies, subtractive methods and precision casting are much faster and produce a superior surface finish. But material savings are a different thing with exotic alloys such as Inconel or titanium alloys.

Hollow, weight- and material-saving parts take advantage of the fact that additive manufacturing enable parts with topologies and structures that are literally impossible, using manufacturing methods used from antiquity through the 20th Century.  One other current use of this potential is in rocket nozzles, allowing parts to be manufactured with internal cooling channels.

This suggests some possibilities for future small arms:

  • A lightweight, insulated barrel comprising an outer sleeve and inner honeycomb compression web, printed around a thin hammer-forged liner.
  • Stronger, lighter stocks and furniture.
  • Weight of rails interfaces reduced by half.
  • Weapons that include printed-in electronic circuitry for fire control (further reduced lock time) and target acquisition and designation. (Imagine a Tracking Point rig, built into the weapon, and the size of a conventional ACOG).
  • 50% reduction in the weight of a heavy machine gun.
  • MG with an evaporative-recovery liquid cooling system built into the rear area of the barrel.
  • 75% reduction the weight of a mortar’s cannon (tube) and baseplate.
  • Improved fragmentation sleeves in grenade launcher and mortar rounds.
  • Built-in recoil compensation for instantaneous second shots or sustained on-target bursts.

Some of these technologies will require engineering not yet done, but none of them appears to require an invention not yet made.

Eli Whitney and Interchangeable Parts

Whitneyville, CT, and the Eli Whitney Armory on the Mill River, c. 1862.

Whitneyville, CT, and the Eli Whitney Armory on the Mill River, c. 1825, by William Giles Munson, 1827. Source: Eli Whitney Museum.

The clothes you’re wearing at this moment are made of fiber. Since the mid-20th century, man-made fibers have become extremely commonplace in textile manufacture. But in all the previous centuries and millennia of civilization, the only possible source for fibers was nature. Natures bounty in providing these fibers is not remarkably varied: the four fibers that are generally made into clothing have been cotton, silk, wool and flax. Silk and wool are animal products. Cotton and flax are grown in the fields.

Cotton_gin_EWM_2007Of these, the last to be economically manufactured was cotton. The nub of the problem is that the desirable fibers are attached to seeds; in nature, they help the seeds spread on the wind. Removing the seeds from the fibers (or vice-versa) was a difficult manual job, uneconomical for even a slaveholding economy. A Massachusetts man and Yale graduate named Eli Whitney invented a machine that solved this problem, just as industry needed it. That’s what the cotton gin (short for “engine”) did: combed the seeds out of the fibers so the fibers could be spun into threads, then woven into cloth, all of that depending on other machines invented by other New England Yankees (and old-England mechanics, too).

A staccato drumbeat of new inventions in the late 18th Century increased the throughput of textile operations over a thousandfold in 20 years, producing industrialist millionaires overnight across the British Midlands, while exhausting existing cotton supplies from India, and giving the dying institution of slavery a new economic boost in the southern States. The efficiency of this novel textile industry was so great that a British merchant in India could ship the raw cotton from Calcutta and receive back finished cloth that he could sell for less than local mills could produce it. It made Whitney rich, but not as rich as it might have done, as intellectual property protections were weak at the time, and his cotton gin was widely copied.

Eli Whitney, 1822.

Eli Whitney, painted from life in 1822.

Whitney was born in central Massachusetts, in the then-unincorporated town which became Westborough in 1717. His birth house was long gone, but his family’s barn stood, in bad repair, until a vandal burned it down in the 1970s. But he did not stay in central Massachusetts and would be associated most of his life with the Connecticut River Valley and especially the State of Connecticut. The Connecticut River and its tributaries were larger and had more drop than the smaller rivers further east, making them ideal for powering machinery.

Whitney turned to another field of invention, one that was the lifeblood of the Valley: gun manufacturing. He knew that placing gun manufacturing on an industrial footing would require specialization, and the only way to do that would be to have parts so standardized that they would interchange without handwork or fitting. This required several enabling technologies to have reached maturity, such as measuring tools, manufacturing parts with tools and dies rather than forging them by hand, and manufacturing to understood, and drawn-to-scale, tolerances.

The explanation is well laid by Whitney’s son, Eli, Jr., in an 1890 letter to the author of a monograph on the cotton gin: 

His invention of methods for making practical and successful his system of making the parts of arms, and any-other article, often repeated in manufacture, is of the utmost importance to mankind, and is undoubtedly the foundation of the mechanical prosperity of the United States, and the superiority of American manufactures over those of any other country.

I refer to his uniformity system—or making the similar parts of an arm or machine so near alike in shape that they can be used in assembling the piece without working. In 1798, when he proposed to make arms with parts interchangeable, the French and English ordnance departments laughed at the idea as an absurdity, saying that each arm would be a model, etc., and would cost $100; but he soon proved the advantages of his inventions, so that the United States government adopted his system in all the armories under its control.

In 1798, there were very few skilled mechanics in the United States, and this uniformity system enabled the manufacturers to employ unskilled mechanics to great advantage. In1856, the British government, and in 1871 and 1872, the Russian, German, French and Italian governments adopted the uniformity system of m^aking arms, invented by Kli Whitney in 1797-98. It has been worth many millions to the United States and the world, but he received a very trifling compensation, scarcely worth mentioning, and that indirectly. At the present time, guns, clocks, watches, sewing machines, and almost every article of wood or metal which is often repeated, is made on the plan of his uniformity system, and it would be a loss of many millions every year for the manufacturers of the United States to go back to the old European system of manufacture.

Whitney did not patent any aspect of his interchangeable parts work, which goes back to his difficulties with the cotton gin. His working model of the machine was stolen, and broadly duplicated; and he found that his patent, for all the pride in brought him, was practically unenforceable. So he chose trade-secret protections instead.

Whitney saw clearly what exactly was difficult about firearms manufacturing to an interchangeable standard:

A good musket is a complicated engine and difficult to make — difficult of execution because the conformation of most of its parts correspond with no regular geometrical figure.

A “stand of arms” was the flintlock-era term for a musket and its accessories (ramrod and bayonet). The accessories had traditionally been hand-fitted to the gun, too: as strange as it sounds to a modern soldier, if you and the fellow in the next rank inadvertently swapped bayonets, you might both be left unable to fix them. When Whitney got a contract for 10,000 stands of arms, with interchangeable parts, in 1798, he had to start by building his factory.

The conversion of metals into ramrods, bayonets, barrels, locks, and “mountings” took place, broadly speaking, in two stages: the first shaping required heat and the second required cutting tools. Except for the barrels, these two processes at the Whitney Armory took place in buildings on opposite sides of the Mill River. On the east bank were the forge fires for the shaping of parts; on the west bank were the machines and tools for the cutting of parts. It is probable that the welding, grinding, and boring of the barrels all took place on the west bank, although the evidence on this point so far is inconclusive, after which they were test-fired in a proof house on the east bank. In Eli Whitney Jr’s day, the heat-treating operations of case-hardening and annealing also took place on the east bank and a foundry was added to the complex of buildings there, to allow shaping by casting as well as by forging. Conversion of hardwood into shaped and “inletted” gunstocks and of softwood into shipping crates took place on the west bank, as did the assembly of the parts and packing of completed weapons.

This comment, from the Whitney Museum site, is admittedly partly speculative; the historians at the Museum admit that there is scant information about the layout and day-to-day operations of the Armory, and that most of what we know about Federal period firearms production comes from the archives of Springfield Armory, where ordnance officers obsessively recorded and filed information that, if it existed at private plants like Remington’s, Waters’s and Whitney’s, was treated as ephemeral and not saved after the plant was reorganized. Whitney’s plant underwent many changes in its ninety years of arms making. The Whitney scholars warn about giving too much credence to inferences drawn from records at the the more-systematized Springfield, but note that:

In 1825… 195 separate operations in musket production were listed in a report about Springfield Armory, and were identified as performed by hand or by waterpower. The number of operations per part ranged from three for the sear to 24 for the barrel. Among them were, for instance, five for the trigger: forging by hand, trimming by water, filing by hand, polishing by water, and hardening by hand. At the Whitney Armory, as we currently understand the site, if a trigger went through the same sequence, it would be forged in the east bank forge shop, then taken to the west bank machine and filing shop for trimming, filing and polishing, and returned to the east bank for hardening before finally joining other parts of the “mounting” in the stocking shop on the west bank. Each of the other 29 musket parts mentioned in the list would follow its own sequence of journeys back and forth across the Mill River for shaping, cutting, and heat treating. Although this seems an inefficient arrangement by modern standards of industrial engineering, it was a far less awkward situation than the one at Springfield, in which the water-powered operations were a mile away from the hill-top location of the manual operations. Eli Whitney had initially acquainted himself with this difficulty at Springfield before deciding to locate all of his musket production at the mill site instead of using his cotton gin shop on Wooster Street, two miles away, for hand operations.

Whitney’s guns still had a lot of hand work in them. In general, parts that could be turned and screw slots on early Whitney muskets show machine tool work, and flat and irregular parts show hand filing. His key innovation may have been organizing the work by type of work rather than by type of gun part. Workers seem to have been specialized, also: if you were a filer, you were likely to be a filer of lock plates, or of triggers, rather than a generalist. And these filers were paid, apparently, piecework rates.

Some machine tool historians also credit Whitney with the design of the first practical milling machine. While claims of primacy are always hotly disputed, it seems indisputable that he did build and employ such a machine in Whitneyville near the end of his life.

Whitney had several descendants who worked in the firearms industry, and who jealously guarded their famous ancestor’s reputation, which makes sorting out man from myth at this two centuries’ remove fraught with complexity.

Other New England makers, such as Asa Waters and Thomas Blanchard of Millbury, Mass., and Simeon North of Berlin, Conn., were also working on interchangeable parts and repeatable machinery at the same time. Blanchard’s stock “lathe” would be adopted practically universally by gunmakers; North would introduce his system to the national armory at Harper’s Ferry. And while the system of interchangeable parts with sizes confirmed by jigs and gages would come to be called the American System, French ordnance officers including Honoré Blanc had already tried to apply similar concepts to the manufacture of cannons and muskets.  (As is commonly the case, intelligent men see a similar need at a similar time, quite independently, but Jefferson knew of Blanc’s experiments and promoted the US contract to Whitney, so the Frenchman may truly have primacy).

Now, during the life of Eli Whitney (up to 1825) there was a limit to what this “interchangeability” meant. A hammer from one of Waters’s muskets might interchange with another Waters musket, but a Whitney musket, which might have been made to the same specifications from the War Department, would have parts that would interchange only with other Whitney muskets. To make truly interchangeable parts, that would be a future step, one achieved in Springfield, Whitneyville, and other facilities by the late 1840s. And it comes at a price: hand-fitted parts often have very tight clearances that ensure repeatability and accuracy. Machine finished parts are often finished to somewhat more open tolerances, trading some “perfection” in the individual weapon for the undeniable benefit of easy parts replacement and repair (and, perhaps, reduced skills required for assembly workers).

By the US Civil War, American muskets and rifle-muskets were made of fully interchangeable parts, as were French and English arms, and other nations were working to the same goal.

So Whitney’s interchangeability was but a baby step. But we can see the ancestry of today’s highly modular ARs, not to mention today’s international-partsbin-mongrel AKs, in the late-18th-Century efforts of Eli Whitney to build a couple dozen muskets that could be disassembled and reassembled after the parts were jumbled. It was taken as gospel at the time that every part of every gun required hand fitting by a gunsmith.

Eli Whitney, then, was a key figure in the transition of gunmaking from hand artisanship to mass production. And one of the delightful and cool things about the gun culture is that he didn’t eliminate hand artisanship; competition from mass-produced guns forced artisans to either raise their quality above that obtaining in the factory product, or to reinvent themselves as designers of guns for production (as John M. Browning, whose father had been an old-style handcraft gunsmith, did).

USMC Door Gun, Afghanistan

Marine Aircraft Group- Afghanistan helps retrograde last of personnel, equipment from Sangin ValleyThis is a great photo by a Marine photographer, taken this month in the sky above our forgotten expeditionary force in Afghanistan. Official caption below; we want to say a few words about the helicopter, and the gun.

U.S. Marine Corps Lance Cpl. Matthew Ghibaudi performs a weapons check from inside a UH-1Y Huey helicopter before providing aerial assault support for ground convoys in Helmand province, Afghanistan, May 3, 2014. Ghibaudi, a crew chief, is assigned to Marine Light Attack Helicopter Squadron 369. U.S. Marine Corps photo by Sgt. Frances Johnson

We came to this via BLACKFIVE.

The Aircraft: UH-1Y ‘Venom’

The Marines are the only service still flying the 1950s-vintage H-1 Huey and 1960s-vintage H-46. But their Hueys have been rebuilt, zero-timed in fact; the airframes born as UH-1Ns were a twin engines (the Sea Services always wanted this for over-water reliability) version, unlike the Army’s old single-turboshaft H-1s (the Army equivalent being the UH-1D/H). Supposedly, 100 or so of the Y models are rebuilt Ns but the Marines have found it more economical to buy all-new airframes than to pay for Bell to disassemble, evaluate, repair and restore clapped-out N airframes, so a lot of these are all-new birds.

The UH-1Y and its sister, the AH-1Z, also have a fully articulating all-composite four-blade rotor system in place of the much simpler two-blade teetering rotor of the H-1, which inherited its rotor system, conceptually at least, from the 1940s-vintage Bell 47. The new rotor eliminates some of the low-G limitations and safety issues (look up “mast bumping”) of the original Huey rotor system. The old bird was safe within its flight envelope, mind; the new one just has a larger envelope.

In the ones based on old airframes, the airframe is gone through, of course, to ensure that it is safe for many more strenuous combat hours, and the powerplant is something a Vietnam Huey driver can only envy.

The Gun: M3M/GAU-21/A

The gun is also an update of an old classic — the John Browning .50 machine gun. The “old” door gun was the M60D, and rather than go to the M240 the Marines stepped up and used the latest version of the WWII- and Korean-vintage ANM3 aerial gun. Gun guys in all services have long known that the parts of M2 and M3 Brownings, and aerial and ground Brownings, have a high interchangeability, making almost all imaginable crossbreeds, variations, and Frankenguns real possibilities — at least, once you get into the war zone and away from the ordnance and supply clerks.

The M3  was an improvement over the Browning M2 (blasphemy!) for aerial and counter-air use. The M3 made a number of changes to allow operation at much higher rates of fire than the M2 in its aerial or ground versions; these changes included a lighter bolt and recoiling parts, much larger and oil-less buffer, relocation of the depressors from the backplate to the sideplates, and an improved, and more positive, feed mechanism that grabs the round front and rear, and can accept belts or chutes. The nominal rate of fire for the WWII ANM3 was 1200 r/min — really rocking for a closed-bolt-firing machine gun. It was available in a flexible model and (more commonly) in a fixed model, where it armed aircraft like the P/F-51 Mustang, the P/F-80 Shooting Star, and the F-86 Sabrejet.

Sole-sourced from FNH USA, the M3M, or GAU-21/A as the Navy terms it, adds a sophisticated soft-mount for the gun and numerous improvements. It replaced an M2-derived gun, the XM218 or GAU-16/A, which had evolved towards the M3 and had a mount of its own. There are many small improvements in the gun, but the big one is that it fires from an open bolt, eliminating cooking off as a potential hazard. The barrel life is claimed to be 10,000 rounds. The  M3M soft-mount also recovers the fired brass, eliminating any risk of foreign object damage, and can be fitted with night vision equipment. The spade grips are attached not to the unsprung gun, but to the buffered mount, making the gun easier to control. The improvements of the M3M seem subtle over the XM218, but they add up to a far more effective weapons system. There is also a fixed version (the M3P) for use in gun pods; these pods are commonly mounted on, among other things, SOF H-60s.

The Rocket Pod: LAU-68

The UH-1Y in the photo also is armed with LAU-68 rocket pods. Each pod carries 7 70mm FFAR (Folding Fin Aerial Rocket) unguided rockets. This rocket, originally known in Imperial units as the 2.75″ Mighty Mouse, has an interesting history of its own, as it originally was intended as an air-to-air weapon for 1950s jet interceptors (F-86D, F-89, F-94, homely and forgotten things, generally) hunting large formations of large Soviet bombers. But it long outlived the Tu-4 threat. Sine then, several generations of 70mm rocket and pod have been used by the US and its allies. A very wide range of rockets are available for helicopter and fast-mover use, and guided rockets are in the final stages of RDT&E. The LAU-68 allows ripple or single fire, but probably will need to be updated or replaced to support guided rockets, if they’re ever actually fielded. And for those occasions where you need to talk to a crowd, and fear that seven rockets may not get your message across, there’s the LAU-61, with 19 of the little beggars to show how much you care.

Wednesday Weapons Website of the Week: Office of Naval Research

Screenshot 2014-05-22 02.27.55Why do a bunch of gun guys want to look at what the ONR is doing? Because the ONR is working on one of our favorite themes: what’s next? By that we mean that current projectile weapons technology is a very evolved version of late 19th century breakthroughs such as breech loading, smokeless powder, fixed ammunition, gas- and recoil-operated automatic weapons, and (for artillery) recoil-managing carriages.

Those inventions revolutionized the weapons of the late 19th and early 20th centuries, and they continue to be exploited even in the latest designs, but the pace of innovation is slower, the effect of innovation is more peripheral or marginal, and the character of innovation is evolutionary, not revolutionary. We could say we’re at a technological plateau, or apogee. (Think of where the internal combustion piston engine was circa 1945 — at a pinnacle of power and efficiency.

Some other trends can be perceived if you look at things in the long (real long) haul. These include a centuries-long trend for projectiles to be launched with smaller calibers, higher velocities, and greater accuracy. But these trends too have hit a plateau.

So the ONR is looking for breakthrough technologies. One thing that they, and the Army, have explored in the past is liquid propellants. We may write something about that, but the bottom line there is that the great potential runs up against insuperable (so far) safety issues. There are many things the next great gun should do, but one thing it should not do is blow itself up.

WNUS_Rail_Gun_Theory_picSo the breakthrough currently being explored is the electromagnetic rail gun. Here is their overview of the program on a single page and here’s a web version. The potential is staggering: 50-100 nm range initially (230 nm stretch goal); Mach 7.5 (5,600 mph). In  gunnery terms, feet per second, that’s 8,370 (2550 m/sec for those of you still using Robespierre’s revolutionary units).  The fastest common To give you some velocity comparisons, that’s not quite as fast as the X-43 scramjet experimental platform, and not quite the orbital speed a geostationary satellite is going. It covers a kilometer in 392 milliseconds. (For comparison’s sake, the fastest guns issued today are smoothbore tank guns firing discarding-sabot fin-stabilized subcaliber penetrators. The APFSDS round in the 120mm M256 gun on the Abrams is pretty fast at 5,500 fps, and the Russian 125mm makes 5,900 fps).

 

 

Navy-railgunORD_Railgun_GA_CONOPS_lg

This is the most recent test video ONR published (last month). Their gun accelerates an irregular shaped projectile to hypersonic speed.

This image, from RIA/Novosti (!) shows the principle of operation in more detail than the image above:

How Railgun works

Its current weakness is its power consumption, but the Navy has the most experience in the world with one potential source of unlimited power: shipboard reactors. The Army, too, is working on railguns, but doesn’t have that handy reactor in its tanks.

The ONR railgun program is now well into Phase II. The Phase I objectives were set, and the Phase II objective is, broadly stated, to transition from a research and development program to an evaluation and acquisition one.

But the railgun isn’t the only thing the ONR is up to, by any means. Writing in the Wall Street Journal this week, ONR head RADM Matthew Klunder reports that, while the railgun will be going to sea in a couple of years, the Navy is already planning to test a laser cannon at sea this year, and is working on other innovations, like unmanned helicopters for supply delivery or medevac.

Advanced technologies that were once the stuff of science fiction are also in the pipeline. This summer the Navy will deploy a laser cannon at sea for the first time and plans to test an electromagnetic railgun on a ship in 2016. The laser cannon delivers an invisible beam of energy with pinpoint accuracy that can take out an incoming plane, drone or boat. The electromagnetic railgun—using electricity rather than gunpowder—will defend against incoming missiles and opposing ships, and project power far inland by launching low-cost guided projectiles hundreds of miles at hypervelocity speeds over Mach 7.

Breakthrough technologies like these give commanders the option to deter, disable or destroy threats from greater distances. In addition, there is no limit to how many rounds a laser can fire, and at just $1 per shot, laser cannons will save the Pentagon (and taxpayers) many millions once fully deployed.

Both the railgun and the laser have the potential to save future ships from the fate of such naval tragedies as HMS Hood, or the USS Maine for that matter, where detonation of a ship’s magazine was a key factor in the loss of ship and men. The railgun can be effective with dumb metal kinetic-energy projectiles, and the laser fires a beam of light — neither is as hazardous to store as plain old HE shells.

Here’s the website, and here’s their YouTube channel (warning, annoying autoplay).