Category Archives: Machine Guns

Bullets with dimples?

Nammo Reduced Range

Nammo BNT 6 Reduced Range 7.62 x 51 mm

We all know that dimples can make a smile irresistible. But a bullet?

Nammo is making 7.62 x 51mm rounds with dimples, and it’s about their physical attraction — sort of. That’s if you’ll accept the meaning of “physical” as in “laws of physics,” and to be more specific, aerodynamics. By making the projectile more physically attractive to the air it passes through — sort of, reversing centuries on progress in making wind-cheating bullets — they can make rounds that work for training on tight, urban ranges.

The Nammo BNT 6 Reduced Range load contains a unique dimpled round weighing 6.2 grams or about 95.7 grains, so it’s very light for a 7.62 round. Its muzzle velocity is in the usual NATO ballpark at 860 m/s (2822 fps). At short ranges (<200m) Nammo claims that the round is equivalent to the usual NATO loads. But it spends its energy very rapidly and can be used in a range fan of only 1500m. (The standard NATO round demands a 4 kilometer range safety area minimum, without safety margins).

The dimples are the key. They are optimized for the round’s Reynolds Number and increase drag two ways, in terms of downrange motion, and, more critically, in terms of spin (which, if we’re doing the back-of-the-envelope right, implies two different RNs based on the different surface velocities). The increased drag and reduced weight make for a projectile that sheds its velocity (both rotational and longitudinal) much more rapidly than normal.

These are quite a different thing from the dimples used to increase the boundary-layer size and reduce drag on golf balls and some experimental target bullets. (Yes, that’s an April Fool’s spoof. And it fooled us on first reading).

Nammo BNT 6 in a belt. (Nammo photos).

Nammo BNT 6 in a belt. (Nammo photos).

BNT 6 is also available in standard links for MG training (including firing from vehicle crew positions), but at present, is only available in ball, not tracer. (A tracer and a “dim tracer” for use with night observation devices are in development). Like most recent Nammo introductions, BNT 6 is “green,” leaving no toxic contaminants behind. BNT stands for “Ball, Non-Toxic,” in the company’s nomenclature, and the BNT 6 projectile reportedly has a soft-steel core only. (Nammo’s combat-load BNT rounds have soft-steel cores with hardened-steel penetrators).

The technology could be adapted to 5.56, at least in theory, if Nammo had a customer for the reduced-range rounds.

Most of the demand for such a round is in Europe, where training areas are at a premium; several European ammo makers often reduced-range non-toxic rounds, although none of them are using the Nammo dimples. (Ruag, for example, uses a near-cylindrical copper round with a central spike). We were unable to find a patent filing for the BNT 6 style projectiles, but suspect one exists.

While the principal use for such reduced-range loads is training, Nammo points out that it’s also useful in urban-warfare and CT applications or “populated sensitive areas,” where minimizing the beaten zone of rounds that miss their targets is a priority.

Wednesday Weapons Website of the Week: NFA Tracker

Screenshot 2014-03-13 08.19.28(Yeah, it’s Thursday. We spent all day Wednesday on planes. Line up for refunds at the refund counter).

This will be the soul of brevity, because it’s really simple. The site, NFA Tracker, is a crowdsourced source of information on how long National Firearms Act registration and transfer approvals are taking.

The NFA is the 1934 act which burdens the possession and transfer of “gangster” weapons: machine guns, short-barreled rifles, and silencers, among others. Each weapon requires a $200 transfer tax every time it changes hand, which was meant, in 1934, as a Pigovian tax that would so burden possession of these firearms as to deter it entirely. Exactly 80 years later, the burden is less a financial one, than one of inconvenience and delay: two hundred 2,014 dollars are a mere fraction of their 1934 ancestors; $200 in 1934 is equivalent to $3,500 today (according to the inflation calculator at Tim McMahon’s, which we’ve found superior to he Bureau of Labor Statistics’ version that we used to use). Well, $3,491.28 if we want to be pedantically precise, but even Tim’s inflation calculator is dealing with numbers that are, by necessity, approximations. Inflation is critical to consider in any longitudinal (i.e. over time) comparison of prices or values; inflation is how governments, deliberately or inadvertently, manipulate the value of their currencies, usually to reward spendthrifts (including governments) by disappropriating savers.

The $200 number hasn’t changed because this part of the gun culture is small, and the use of legal, registered NFA weapons is below-the-radar, so that the few politicians that care enough to either increase or decrease the burden on these few individuals. The one Congressional change to the NFA came in 1986, when the manufacture of new machine guns was banned (like all NFA laws, government entities are exempt).

ATF appears to play a game with NFA registrations. When their preferred politicians are in charge, they drag out the paperwork time until it now takes almost a year — a good 11 months — for a Form 1, Form 4 or even a Form 3 to be approved. They can’t stop following the NFA statute, but they can stage a slow-down strike, and that’s going on right now — something we can see from data. There is no place to appeal or complain to, and it’s widely believed in the community that complaints delay your registration further, getting in placed in an FU File. An organization that represents some NFA owners, the NFATCA (National Firearms Act Trade & Collectors Association), tried to work with and cozy up to the ATF on NFA issues, with the end result that the ATFs recent proposed rule burdening NFA Trusts came out with an NFATCA imprimatur on it,  a calamity from which NFATCA panjandrums backpedaled furiously.

E-filed forms go quicker, without actually going quick, but you can’t  e-file unless you are a corporation or trust. This is NFA Branch’s way of throwing a bone to those clients most likely to have a complaint heard by our coin-operated Congress. Combined with the ATF’s recent stroke-of-the-pen rewrite of the corporation and trust rules, which significantly burdens those entities, it’s all part of a master plan to deter NFA weapon and accessory ownershio.

Apparently it’s not working, as short barreled rifles and silencers are making record sales, and the ATF’s policy of deliberate slowdown is compounded by a higher workload than that to which the payroll patriots in West Virginia are accustomed. So the trend is for even longer delays ahead.

The advice that comes out of a study of NFA Tracker data, then, is to apply as early as possible so at least you’re ahead of the next guy in what’s soon going to be a year-plus-long line.

OK, where to find the data?

The basic NFA Tracker page is straightforward:

Screenshot 2014-03-13 09.35.36


While the basic page gives you a glimpse of what’s been logged lately, the real power of the site comes when you log in (free) and use the easily-overlooked tabs along the top. The two-year delay trend shows how the delay on Forms 1 and 4 exploded after November, 2012. (Did something happen in November, 2012?)

NFA Tracker 2 year delay trend


A look at the longer-term shows that the Great Delay of 2013™ is only the second such since NFA Tracker began operating. There was another Great Delay of 2010-2011™ and the trend is clear, even though the data from NFA Tracker’s early years is a bit sparse.

NFA Tracker extended delay trend

That’s what’s going on in the NFA world. Approval times have soared from three months to a year over the course of the last administration. Old-timers remember a similar delay trend, althogh it didn’t make it past nine months or so, beginning circa 1993-94, but by the mid-oughts ATF had the paperwork more or less caught up.

Naturally, as participation in NFA Tracker grows, the quality and reliability of its data also grow, something you can infer by the density of the dots on its scatter plot. We participate and strongly urge you to do so, if you’re in this market (and if not, why not?)

NFA Tracker also maintains a Facebook page that can be of some use, especially to those who use that site.

Meet the BAR – in depth with the IMT

The Institute of Military Technology (the museum that spun off from Reed Knight’s amazing collection) has produced this video on the BAR, which includes some period training film and slide footage, Reed Knight himself going over the mechanism, and… best of all! Live fire.


We may be limited in what we can write this week (especially first half…) and we owe you TW3s for the last two weeks. And last week’s Saturday Matinee. Arrgggh, that’s all we can say to that right now. And that we’ll let you know when the backdated stuff goes up. In the meantime, enjoy the BAR.

St. Valentine’s Day Massacre Guns on display — today

The two guns, still held by the Sheriff's Department that captured them, are usually locked in this cabinet. Image source.

The two guns, still held by the Sheriff’s Department that captured them, are usually locked away in this cabinet. Image source.

The Mob Museum, which is appropriately enough in the Mob’s own creation, Las Vegas, is displaying two submachine guns that were part of the St. Valentine’s Day Massacre today.

The Massacre answered the 1929 iteration of that perennial underground question, “Who will be the boss?” Seven Bugsy Moran goons were blown away by Thompson-wielding members of Al Capone’s gang. The fate of most of the guns used by the Capon goons is unknown, with two exceptions. The Museum’s press release:

LAS VEGAS (January 2014) – This Valentine’s Day, Friday, Feb. 14, The Mob Museum, The National Museum of Organized Crime and Law Enforcement, celebrates its second anniversary with two-for-one admission to out-of-town visitors and FREE admission for Nevada residents. In addition, at 9 a.m. that day, the Museum will have the official unveiling of a limited-time-only presentation of two Thompson machine guns used in the St. Valentine’s Day Massacre in 1929. Lt. Mike Kline from the Berrien County Sheriff’s office in Michigan will deliver presentations about the artifacts. The public presentation schedule follows:

Friday, Feb. 14: 11 a.m., 2 p.m. and 6 p.m.

Saturday, Feb. 15:  11 a.m., 2 p.m. and 4 p.m.

Museum Members also will have a chance to attend an exclusive showing of the two Thompson machine guns on Saturday, Feb. 15 from 9 to 10 a.m.

The artifacts go hand-in-hand with the St. Valentine’s Day Massacre Wall that has been part of the Museum’s collection since its opening on February 14, 2012. In Chicago’s infamous St. Valentine’s Day Massacre of 1929, seven members of Bugs Moran’s gang were lined up against this wall, shot and killed by Al Capone’s gang.

The two machine guns, numbered #7580 and #2347, were first positively identified by Colonel Calvin Goddard, forensic scientist specializing in ballistics, in December 1929 after investigating many Thompson guns found in the Chicago area. These two guns, on display at the Museum Feb. 14 and 15, are the only guns ever scientifically proven to be part of the 1929 St. Valentine’s Day Massacre.

Thompson #7580 was marked Exhibit “A” and was determined to have fired one 20-round magazine at the Massacre scene. Thompson #2347 was marked Exhibit “B” and was determined to have fired one 50-round magazine at the Massacre scene.


Mob Museum BuildingThe Museum has also displayed another artifact, a Colt Detective Special believed to have belonged to Frank Gusenberg, one of the ventilated Moran men. The Museum’s building is a restored former Federal Building and courthouse in which, appropriately enough, historic hearings on organized crime were held by the Kefauver Committee in 1950.

But we’re gun guys, and it’s the Thompsons interest us. Turns out they were seized by the Berrien County, Michigan, Sheriff’s Office from the house of Fred Dane — who police had learned was really a notorious robber and murderer named Fred “Killer” Burke. (That’s rare example of someone nicknamed “Killer” being an actual killer. And he wasn’t born Fred Burke, although that was the name he’s known by now, and the name he’d take to prison. Like Lenin, he made the alias famous. He was born Thomas Camp). “Dane” wasn’t home, but the police grabbed “Mrs. Dane” (Burke’s girlfriend) and a bunch of things. “Dane,” who they now knew was Burke, was wanted for the murder of a Michigan cop who’d pulled him over.

Burke's house today still stands as a real estate office (BCSD photo).

Burke’s house today still stands as a real estate office (BCSD photo).

When they caught up with him, Burke was delighted to be arrested — he thought the cops were other gangsters intent on whacking him, and they were Michigan cops (at the time, Illinois, where Burke had done a lot of business including the Valentine’s Day massacre, enthusiastically applied the death penalty, and “enlightened” Michigan had none). Burke would die of heart disease and diabetes in a Michigan prison in 1940, and never did answer for his out-of-state crimes.

Meanwhile, inside Burke’s house, the Sheriff’s department had found some considerable evidence, including:

Arnenal inside Burke's homeTwo Thompson machine guns w/ Nine ammunition drums – One gun was assembled, loaded and ready for instant use while the other was in a black suit case

Five 100-shot .45 caliber drums loaded, many other smaller drums

Three 20-shot clips

Two high powered rifles, one was Winchester .350 automatic, other was Savage .303

One sawed off shotgun with pistol grip

Two bags of ammunition estimated at 5,000 shells

½ dozen fruit jars and tin cans filled with misc. ammunition, including smokeless shotgun shells, shells loaded with iron slugs and small shot.

½ dozen tear gas bombs

BCSD Historian Chriss Lyon with one of Burke's guns.

BCSD Historian Chriss Lyon with one of Burke’s guns.

Both of the Thompsons were Model 1921s, one with Cutts Compensator and one without. The deputies also found money, bulletproof vests, and other artifacts; and one Colt 1911 not listed in the inventory can be seen in photos. The Thompsons posed an identification problem: both had had their serials defaced, as had some of the drum magazines.

Calvin Goddard of the Northwestern University Scientific Crime Detection Laboratory raised the serial numbers with acid, and learned that the Cutts gun was Number 7580 and the other was 2347.

Crime labBut they could still learn more from these guns. Goddard’s technicians fired the guns into hampers of cotton. Then they examined the rounds and matched them to crime scene bullets. This was routine — for them — and they’d already done it with many Chicago-area recovered Tommy guns, as well as many hundreds of pistols. But the two guns taken from “Killer” Burke’s house were the only two ever ballistically matched to bullets recovered at the scene of the Valentine’s Day massacre. (They already had a pretty good idea that the massacre weapons had been Thompsons, as that and the S&W 1917 were the only .45s at the time with a right-hand twist, and a 1917 wouldn’t have left dozens of cartridge cases behind). They were able to match one gun to 20 bullets — the size of a standard Thompson stick magazine — and the other to 50, indicating that Burke, or somebody, emptied an “L” drum from it at the doomed Moran loyalists.

Goddard examining a .45. Note TSMG in background.

Goddard examining a .45. Note TSMG in background.

The next question was: where had the guns come from, and how had they gotten into criminal hands? What we learn is that the sources of crime guns even then included diversion from lawful commerce, and acquisition via corrupt law enforcement officers. The coroner’s inquest, via the  Berrien County SD again:

Thompson serial #7580 was shipped from Auto-Ordnance Corporation of New Haven, Connecticut on October 19, 1928 as part of a shipment of three Thompson submachine guns, serial #6926, #7580, #7699. This shipment also included three “L” type fifty round drum magazines.

Shipment was received October 23rd by Peter Von Frantzius Sporting Goods of 608 Diversey Parkway, Chicago, Illinois, a noted Sporting Goods dealer in the area. On October 23rd, a “dummy” box was shipped by Railway Express to one Victor Thompson (aka Frank V. Thompson), of Fox Hotel, 100 Douglas Avenue, Elgin, Illinois. This entry in the ledger would account for the destination of the three guns. As agreed the serial numbers were filed off by gunsmith Valentine Guch at a cost of two dollars for each gun.

Frank V. Thompson (aka F. V. Thompson, Victor Thompson, Frank Russell), paid cash and took the guns over the counter on October 23, 1928. These three Thompsons were in turn sold or delivered.

This “dummy” package had been at the Railway Express office about seven months. The package was subpoenaed May 4, 1929 from the American Railway Express Company in Elgin, Illinois by Officer Frank Donahue of the Chicago Police Department. It was kept sealed until brought into the Jury room, then opened in the presence of the Coroner’s Jury. The box alleged to hold three Thompson submachine guns was actually found to contain some excelsior and four bricks but no Thompson submachine guns.

Frank V. Thompson testified in 1929 at the Coroner’s Inquest that Thompson submachine gun #7580, with numbers removed, was sold to a Bozo Shupe of Chicago. When confronted by the Chicago Police Department, Bozo Shupe refused to testify or make a statement. Sometime later, he was found murdered on the west side of Chicago near Cicero. At some point, Thompson #7580 passed from Mr. Bozo Shupe to Fred R. “Killer” Burke (aka Fred Dane) of Stevensville, Michigan.

Von Frantzius appears to have been a crooked dealer who supplied many Chicagoland mobsters with the tools of their trade. Certainly shipping a fake package of guns to rot in an Express office, waiting for someone to call, while delivering the guns over the counter, indicates complicity. We don’t know what happened to him. Today he’d get 10 years for every gun, but there were no Federal gun laws in 1929.

The other Massacre Thompson took a different path to the Massacre. It sold over the counter to a Deputy Sheriff on 12 Nov 1924. The Deputy, Les Farmer, was associated in some way with an organized crime group. More details at (Expect to spend some time there — very cool site and it was very helpful in telling this story).

Both of the guns are today in the possession of Berrien County Sheriff’s Department still, as are many other Burke artifacts including bulletproof vests. (Yes, nothing’s bulletproof, but that’s what it says on the tags. Their technology is probably worth a post sometime).

Valentine's Day Massacre

The St. Valentine’s Day massacre was a watershed event. The shock of a mass killing of seven, even with all the victims being gang members, was spread nationwide by radio, making this arguably the first national mass-murder media exploitation event. This created demands, fanned by the same media, to do something. At least three somethings flowed from this:

  1. The politicians whose Utopian fantasies had produced Prohibition with all its unintended (but predictable) consequences attempted to extend that prohibition to “gangster” firearms, which they originally defined as MGs, short-barreled long guns, and handguns. They would let handguns drop off their proposal for fear of the National Firearms Act being found unconstitutional.
  2. Other politicians (and some of the original Prohibition supporters, who were now awake to the real consequences of their airy dreams, now supported Prohibition repeal. It ultimately became a partisan issue (for those of you who see political parties as “our team” versus “their team,” it was the Democrats on the repeal side of this and the Republicans going down with the ship of Prohibition). This decision was the key to ending the Gangster Era, and wise bootleggers and their gangsters (like Joe Kennedy) turned to less violent pursuits. Unwise ones, like Bonnie and Clyde, “Machine Gun” Kelly, and John Dillinger, turned to bank robbery or other violent crimes; they wound up dead or in prison before the end of 1934.
  3. Law enforcement, especially Federal, grew enormously, and developed its culture during this period, and they were vastly enlarged and emboldened after the massacre. This included such positive developments as Goddard’s Northwestern U Scientific Detection lab, which was taken over whole by the then-forward-looking Chicago Police Department. But there were also lasting troubles that were born here. The Federales’ budgets grew to some $40 million a year in 1932, almost $700 million in 2014 dollars. Today, the Capone gang is as dead as the Moran gang, but the surviving ATF culture of break-the-law-to-enforce-the-law stems directly from this period and has produced such scandals as “testilying” about the accuracy of the NFRTR, the systematic gunwalking of Wide Receiver and Fast & Furious, and the many abuses (including more gunwalking) in the agency’s storefront operations.

So these aren’t just two tommy guns. They’re artifacts of a historical inflection point.

For More Information

Even though his Thompson book is out of print, gun writer Frank Iannimico’s site has some information. He’s a big TSMG fan. His former forums are now at

The Thompson Collector’s Association is a gold mine of TSMG expertise.

This shop offers Tommy Gun gunsmithing, including rebuilding semi 1927s to more closely resemble the original M1921, including SBR/removable stock conversions.

There are a lot of books about Al Capone, take your pick, but Chriss Lyon (pictured above) has one coming on the life and times of Fred Burke.

Here is the grandpappy of your M240

Larry Vickers runs through the history of the Browning Automatic Rifle. Three minutes.

In our time in the Army, we were brought up by Vietnam era or earlier vets who swore by this thing. Because they still existed in strategic caches and other storage, they were still part of the SF weapons man’s qualification until the end of the strategic cache program in the 1990s.

As Vickers relates, the BAR underwent no major changes throughout its official wife, which lasted from 1918 to 1958. The bipod and carrying handle were added, and an option for semi automatic fire was deleted, because at the slow rate of fire, it was easy to fire single shots by trigger manipulation. Those changes were complete by the mid-1920s, and the BAR was the base of fire of the infantry squad throughout World War II and the Korean War.

Even after the nominal replacement of the BAR by the M60 GPMG, National Guard, ARVN (both until circa 1970), and other foreign armies continued to use the ancient weapon. The Army’s replacement for the BAR in the squad automatic rifle role was for many years simply a standard infantry rifle, M14 or M16, fired in the automatic mode. This was unsatisfactory, especially to old-timers who remembered the BAR, and went to the development of the SAW. The Marines have since reverted to a rifle as the squad automatic weapon, the M27 IAR.

BAR men swore by their weapons, and SLA Marshall, whose research was very influential despite the later discovery that much of it was faked, did make the claim that fire in an infantry squad usually began at the BAR gunner and spread from him to the other squad members.

The BAR was the first US weapon to be frequently shipped with a plastic stock, beginning in 1944. The plastic BAR stock is designed to be the same weight as the original stock of black walnut, but is significantly stronger. (Plastics and composites would not be exploited for weight reduction until the later M14 rifle program).

The BAR was not without its limitations. While it was very reliable, it was complicated. We SF students had 78 parts to account for, disassembling the BAR against a time standard — something that was possible, but challenging. It was also very heavy for an infantry automatic weapon.

The BAR  managed to live on, in a way. While BARs were built, in peacetime, by Colt in the USA, the same design was made for the European market by Fabrique Nationale d’Armes de Guerre in Herstal, Belgium. Many BAR aficionados consider the FN Model D, which was available in several calibers and had a pistol grip, to be the ultimate BAR.

Its reliable mechanism was inverted by FN designers (M. Saive and M. Vervier) and used as the basis for the belt fed MAG general-purpose machine gun. That of course has replaced the dreadful M 60 in United States service, and been subject to many other developments since then.

Hat tip: Bob Owens at


The only failure is the failure to tripod

Sorry about the title. In-joke. But hey, there’s a new tripod in town, and it works with the M2HB and M2A1 machine guns and also the Mk19 grenade launcher. This is kind of big news, because the M3 it replaces was type-classified in 1934. FDR was president, most of the world’s fighter planes were canvas-covered biplanes, and the armed services were roiled with debate over whether such newfangled ideas as multiengine bomber aircraft, tank and motorized forces making independent breakthroughs, and aircraft carriers would ever really catch on.

The Spanish Civil War, where all those things except carriers would get a thorough shakedown, was in the future. So was the Italian campaign in Abyssinia. Most of the babies born in 1934 are now on the Social Security Death List… so maybe it’s time for the venerable M3 tripod to join them. The new ‘pod is called the M205 and it borrows a couple of ideas from foreign tripods, plus a few twists of its own, to save 16 pounds.

At 34 pounds, the new M205 is 16 pounds lighter than the 50-pound M3 Tripod. The tripod also has an integrated Traverse & Elevation (T&E) mechanism that allows faster, more accurate target engagement. Soldiers can even operate the T&E with one hand to make bold or fine adjustments. There’s also an adjustable traverse limit stop, which controls left and right fields of fire. The T&E’s clear, readable scales enable the operator to quickly establish a fighting position’s field of fire limits with a properly annotated range card. The lightweight pintle also allows greater weapon elevation and depression than the M3 pintle and the tripod has a built-in pintle storage slot to prevent loss when stowed.

The tripod appears to be sturdier than the heavier one it replaces. The new T&E is similar to the one on the new M192 tripod used with rifle-caliber MGs, and it lets you aim the gun more precisely, more rapidly, over a wider range, and — a great boon to everyone who positions machine guns — lets you quickly set left and right limits.

A machine gun with a T&E and a scope is a weapon capable of sniping, as Carlos Hathcock proved in Vietnam. A better tripod and T&E, coupled with the new self-headspacing M2A1 gun, answers a lot of the beefs that soldiers have had with Ma Deuce for almost 100 years.

The M205’s design makes it a very stable platform, which is a key factor for accurate engagements and conserving ammunition. The front leg rotates in 6 degree increments and, combined with the adjustable rear legs, can accommodate all types of terrain. There are also spades on all three feet, which allow the tripod to dig into dirt and sand while firing.

The rotation of the front leg and the extensible rear legs will look familiar to anyone who’s ever set up a PK tripod. The M205 looks a lot better built and more smoothly functioning. It remains to be seen how well it holds up.

SGT Gary Huerta, E FSC, 1-41 INF, 3/1AD, also attended the “New Equipment Training” event. With his seven years of service in the Infantry, Huerta appreciates the big improvements in the tripod’s weight reduction and portability. When stowed, the tripod collapses to 46 inches long, and is just 8 inches high and 12 inches wide – less than 50 percent of the M205’s deployed height and width.

“The M205 has more moving parts, but is pretty strong and portable,” said Huerta. “The M3 would flop around on you when you needed to carry it. That doesn’t happen with the M205.”

The Army will be replacing all M3 tripods over the next several years beginning with near-term deployers. In the coming months, more M205 fieldings are scheduled at installations such as Fort Campbell, Fort Hood, Fort Carson, Fort Richardson, and Fort Riley.

via “Ma Deuce” Gets a New Stand.

Some folks may point out that the old tripod was perfectly functional. And indeed, it was; these new ‘pods just provide some incremental benefits, and nothing really big — except for that one thing.

That one thing is the weight reduction. Any time you can take 16 pounds off a grunt’s back, you shouldn’t let the opportunity slide.

A Short History of Chrome Bores

For some 500 years it’s been known that rifling would impart spin and therefore stabilization to a ball or bullet. Spiral grooves probably evolved from straight grooves only intended to trap powder fouling; by 1500 gunsmiths in Augsburg, Germany, were rifling their arquebuses. This gave rise to an early attempt at gun control, according to W.S. Curtis in Long Range Shooting, An Historical Perspective: 

In the early 16th Century there are references to banning grooved barrels because they were unfair. Students of the duel will recognize this problem arising three hundred years later.

Curtis, 2001. Curtis notes that why rifling was twisted is unknown, and that it may have been incompletely understood. He has quite a few interesting historical references, including one to a philosopher who explained that if you spun the ball fast enough, the demon (who dwelt in gunpowder, which was surely Satan’s own substance) couldn’t stay on and guide your ball astray. (Curtis’s work is worth beginning at the beginning, which is here).

By the mid-19th Century, the Newtonian physics of the rifled bore had been sorted out, the Minié and similar balls made rifled muskets as quick-loading as smoothbores, and the scientific method allowed engineers to test hypotheses systematically by experimentation. So smoothbores were gone for quite a while (they would return in the 20th Century in pursuit of extreme velocities, as in tank guns).

Rifling had several effects beyond greater accuracy. It did decrease muzzle velocity slightly, and it did increase waste heat in the barrel. The first of these was no big deal, and the latter was easily handled, at first, by improved metallurgy. But rifling also helps retain highly corrosive combustion by-products in the bore; and corrosion was extremely damaging to rifling. Pitted rifling itself might not have too much of an effect on accuracy (surprisingly), but the fouling that collected in the pits did. Corrosion also weakened the material of barrels, but most military barrels had such great reserves of strength that this was immaterial, also.

Fouling and pitting have been the bête noire of rifles from 1498 in Augsburg to, frankly, today. A badly pitted barrel can only be restored by relining the barrel, a job for a skilled gunsmith with, at least, first-class measuring tools and a precision lathe with a long bed. Relining has never been accepted, to the best of our knowledge, by any military worldwide.

Chrome Plating is Invented: 1911-1924

One approach has been to use corrosion-resistant materials for barrels, but that has been late in coming (late 20th Century) because it is, of course, metallurgy-dependent. Early in the 20th Century, though, American scientists and engineers developed a new technology — electroplating. George Sargent, of UNH and Cornell, worked with chromium as early as 1911, and Columbia scientists developed a commercially practical process of using electrodes to deposit chromium by 1924. Meanwhile a New Jersey professor worked with a German process.

The two groups of professors formed start-ups, the Chemical Treatment Company and the Chromium Products Corporation. At this point, chrome plating has not been applied to firearms. Electroplating had been used for guns for decades, of course, but that was nickel plating — eye-pleasing, but soft and prone to flaking, not suitable for bores, and not remotely as corrosion-resistant as chromium.

(This article is rather long, so it is continued after the #More link below. We next take up the application of this process to rifle bores).

Continue reading

Foreign & Obsolete Weapons Training

SF NCOs conduct mechanical training on AK rifles for troops of the Malian Army.

SF NCOs conduct mechanical training on AK rifles for troops of the Malian Army.

When we attended what was then Light Weapons School (then Phase II of a Weapons Man’s SFQC), the stress was on mastering the mechanical operation and employment of foreign and obsolete small arms. Given the environmental changes of the last thirty years, the current course has lots more shooting and teaching-of-shooting (big improvement), lots more base defense and tactics, includes heavy weapons training including weapons that were then-novel and not included in a Heavy Weapons NCO’s training (like ATGMs and MANPADs) and is nearly twice as long. (In 2014, it becomes fully twice as long).

One of the things that’s been cut to make room for the course improvements, is a lot of the foreign and obsolete weapons training. We understand why, but believe that foreign and obsolete weapons training is good for not only SF but also for other members of combat units.

In World War II, paratroopers were taught to manipulate the enemy’s small arms, and that seems like a no-brainer. For SF, who are likely to operate with irregulars armed in part via battlefield recovery, this is obviously important, too.

Foreign weapons mechanical training has the following benefits:

  1. It builds confidence in US weapons, which are equal to or better than their world competitors at this time.
  2. It enables troops to use Allied and enemy weapons should they be required to in combat.
  3. It gives troops a chance to see foreign weapons at all ranges, including up close, and at all angles, increasing their ability to identify foreign equipment from photographic or personal reconnaissance.
  4. It demystifies foreign, especially enemy, forces to see and handle their weaponry.
  5. It is mentally engaging and physically confidence-inspiring.

Mechanical training is good, but to take it to the next level, the combat unit should consider foreign weapons firing training. This requires more instructors, armorer-certified weapons, ranges, and ammunition.

Foreign weapons range firing does all the same things that mechanical training does, and adds benefits to each. For example, attempting to zero and fire an AK for record makes one truly appreciative of the sights and inherent accuracy in the M16 and M4 series of weapons.

Live fire training does additional things besides.

  1. Accustoms the students to the sound of enemy weapons. Most enemy weapons have distinct reports that experienced combat troops learn to recognize. Firing foreign weapons on the range accelerates this learning so that it need not be done under fire and at great risk. Along with the individual sound of gunshots, most auto weapons have distinct rates of fire. This benefit is amplified if the troops can hear the weapon from distinct angles safely, particularly from downrange (i.e., in a target-butt trench).
  2. Accustoms the students to the sight of enemy weapons. (Dust, muzzle flash by day and night, distinct tracer appearance, etc).
  3. Prepares the students much better to fire a battlefield-recovered weapon, should that be necessary.

Obsolete Weapons training has fewer distinct benefits, but is still helpful.

  1. It helps them position current US weapons longitudinally in weapons and technological history.
  2. If enough versions of weapons are available, it can prepare students for an encounter with novel weapons, by giving them a wide range of operating principles and maintenance procedures to consider.
  3. It does help in those environments where obsolete weapons are likely to turn up — a set which includes many war zones. For example, Czech ZB-26 light machine guns, Egyptian “Port Said” copies of the Carl Gustav M45B submachine gun, and long-obsolete Russian DP-series machine guns were widely encountered in the early days in Afghanistan. Long-outdated M1 Carbines still turn up worldwide, as do STEN guns; Syrian rebels found a cache of German MP-44s.
Marine fires a PKM light machine gun in training provided by International Police Supply, a contractor.

Marine fires a PKM light machine gun in training provided by International Police Supply, a contractor.

While the US Army once had the capability to conduct this type of training, it destroyed its in-house capability with multiplying and metastasizing bureaucratic regulations. At one time, to fire a foreign weapon, it needed to be “certified” by a specific office at Aberdeen Proving Ground. The office granted a one-year certification that took over a year for them to issue, so that you needed to have three of any given weapon in order to have one available to shoot regularly. In practice, any gunsmith or armorer with his ordinary tools and a set of headspace gages should be able to pass judgment on the safety of a foreign or obsolete gun.

As a result of the Army’s mismanaging its own capability to provide this sort of instruction, a niche has opened up for contract providers. The problem is, of course, that armed forces units seldom have the budget to engage such a contract provider.

The SAWs That Never Was, Postscript: Civilian SAW

So, you want a SAW. Maybe a Mk46.


Well, you could enlist with the Ranger Option… OK, OK, we hear ya. Most of the guys who read this can’t do that for one reason or another. Like they used up their NCAA combat arms eligibility. Or used up their body, already. Or are a bit on the old side for enlistment. Or are a bit on the anti-authority side. (In which case, consider SF). Or you are a citizen of another country — the globe holds a couple hundred of them, and every one has its charms, and a dedicated (and usually patriotic) gun nut or two.

Well, wouldn’t it be neat if there were a civilian-legal, semi-auto SAW you could buy in the USA as a Title 1 firearm? Well… there is. The guys at the US Machine Gun Armory (a private business, associated with the guys that bring you Small Arms Review and the Small Arms of the World website) reverse-engineered a Minimi about five years ago and by 2009 had ATF approval of a closed-bolt, hammer-fired, US-legal semi-auto SAW. In fact, the gun pictured at the top of this article is one of theirs. There’s a giveaway that it’s not a standard FN SAW.


ATF requires civilian semi-auto guns to fire from a closed bolt, and generally prefers a rotating hammer to an inline striker. The guns, if based on a prototypical machine gun, must be so designed as not to readily accept MG internals. MGA pulled this off by adapting the H&K semi-auto mechanism as used in the HK91, and making some modifications to the receiver: “the right bolt rail is thicker, the trigger hole is about a quarter inch longer, and there is a brass bushing in the trunnion.” The first two mods prevent use of an MG bolt carrier or trigger group; the third is required because of modifications to the operating rod.

Screenshot 2013-12-03 17.08.03

That’s the give-away in the picture above — the deep HK grip piece instead of the shallower FN piece.

Of course, they can also make full-auto guns for government customers, and this enables one thing that didn’t previously exist: a semi-auto setting on an MG’s selector, if the customer elects closed-bolt operation. This should appeal to some police customers.

“Ah, but what’s it cost?” you may ask. And the cost will relegate this gun to most readers’ Dream Cabinet instead of their Physical World Cabinet. They originally quoted a price of about $22k and you could, probably, run it up to that level with enough slick options. But entry level is about $10k, making it competitive with some other belt-feds like the M60.

“Ah,” you say, “but the M60 is in the mighty 7.62 NATO.” Well, next year, they’ll have guns and conversion kits in that caliber, too, just like the Mk46′s big brother, the Mk48. They already have .300 Blackout and 6.8 conversions. Other options include an M16-mag magwell (which they warn doesn’t work, just like FN’s original; and they don’t warranty), an M249-style forward tripod bushing (which is not part of the lightened Mk46), and several kinds of stocks and barrels, including rare Mk46 16.3″ barrels as used by the SEALs .

California Legal — for now

Right now, they’re pushing their California-compatible gun, which has no “assault rifle” features. That’s the good news, for you fruits and nuts in the great granola bar that hugs most of the Left Coast. The bad news is, it’s only legal till the end of the month. If you own and register the gun by New Year’s Eve, you’re grandfathered in; miss that boat, and you’re locked out by the California beltfed ban which takes effect on 1 January. If you can’t afford the whole gun, you can just buy the receiver now and register that, and the other parts follow when you can swing ‘em. (Below: receivers without and with the optional tripod bushing).


Several other attempts at building civilian SAWs have been made, or at least promised, over the last six or seven years. The only one we know of that’s still running is  US Machine Gun Armory.


The Joys of Document Diving / Army Procurement circa 1979

If you were paying attention during our recent series on the Army’s Squad Automatic Weapon program of the 1970s, you’ll be able to tell what’s wrong with this guy’s gun, or at least, with the caption to it. The caption says: “XM248 Squad Automatic Weapon will be evaluated with other contenders in 1979.” And here’s the picture. Despite its graininess, the error is clearly visible. Can you spot it?

Screenshot 2013-11-30 20.32.37

The error is this: that’s not an XM248 the grinning soldier is holding. If you remember our series, the principal changes from the XM235 included the relocation of the pistol grip aft from its original position on the longitudinal center of gravity, and to the right of the belt-box feed, which is also on the longitudinal center of gravity, but offset to the left. The Army didn’t like this asymmetric arrangement because it locked the approximately 10% of soldiers who are left-handed out of SAW positions (or required the to fire off the weak shoulder, at least). But that change also weakened the notably pleasant handling characteristics of the XM235 — which might just be the reason that soldier is grinning. Yes, the “XM248″ in the picture is an XM235 — even though the identification is in an official Army document, it’s wrong.

It happens.

Screenshot 2013-11-30 20.47.21The caption error is to an article that is interesting in its own right, despite a very dry title: “An Overview of Small Arms Technology” by COL Charles J. Garvey, in the May-June 1979 issue of Army R, D, & A magazine. The mag, since merged with other Army publications, was aimed at insiders in the Army Research, Development & Acquisitions community — the guys, and even then some gals, who test and buy stuff for the Army.

That issue had a small arms theme, as the cover shows, and Garvey started off on an optimistic note — before dropping the hammer on his fellow procurement officers. “Small arms technology has significant potential for improvement and must be exploited by placing renewed emphasis on production and research and development planning in this area,” Garvey wrote. But he made it clear that the Army wasn’t living up to that potential:

The area of small arms is perceived by some as part of a hobby shop syndrome versus an area of real technological significance. When one reads the program summaries they read the same year after year. One question becomes evident,

“What has the small arms community produced in the last decade?”

We have spent millions of dollars and- uncountable man-years and, to the best of my knowledge, the 30mm GAU 8 round is the only system produced in the recent past. However, I do realize that the 30mm ADENIDEFA, the 25mm Bushmaster and the squad automatic weapon system are in the later stages of development. Need I even mention that an industrial firm with such a record would have filed for bankruptcy years ago?

Our challenge is to significantly advance small arms technology in the next decade. We simply must. Who is at fault? We are! Our traditional policy of each service determining its own requirements, running its own labs, and fighting for its own budget has led to inefficiencies, duplication, and parochialism in a number of instances.

Garvey went on to identify some problems that are and remain with us today:

  • RDT&E projects and procurement cycles are long, but command and staff tours are short, and commanders focus on short-term objectives.
  • “The best is the enemy of the good” in that the armed services have a tendency to tinker endlessly rather than cut off design changes and actually field improved weapons.
  • The Army can’t generate quantitative and qualitative data demonstrating the war utility of foot soldiers and their arms and equipment, and time and money spent trying to develop such into usable metrics has failed.
  • The services spend a lot on customizing weaponry for competition, but competition tuning doesn’t translate into combat utility: “[W]e need reliability, accuracy, ease of maintenance and operation obtainable by any soldier, not just a skilled weapons technician, and those systems must be capable of being mass produced.”
  • In a harbinger of the future SOF Truth, Humans are more important than Hardware, Garvey hammered on combat usability, something that was a problem with many 70s systems such as early ATGMs. “In the future we must insure that our technological advances can be made compatible with the average soldier. To do less is self-defeating, regardless of the technical capability of the weapon system.”
  • He recognized the budgetary environment the Army of 1979 lived in: “[T]he fastest and least expensive method of impacting readiness today is to modify present inventory. This is the wave of the future.” This is pretty much the budgetary environment we’re headed into next, also.

He also had a few things to say about procurements that didn’t go well: one that was botched entirely, and one where delays cost the Army and the nation a fortune:

[L]et’s not have another M219 armor machinegun fiasco. During the early 1970s we product improved that weapon with 19 separate modifications. This resulted in very little change in performance.

A classic example of schedule delay and indecision is the Bushmaster automatic cannon program for the Army’s Infantry Fighting Vehicle.

Following side-by-side tests of three candidate guns, the decision was delayed for two years to permit a re-evaluation of the program. The result was increased time and money and the taxpayer was made to pay again for these decisions.

Ironically, he thought the SAW program, which had been running off and on for over a decade as he wrote his story, was one of the success stories. Given that the SAW ultimately did work, maybe he was right.