Author Archives: Hognose

About Hognose

Former Special Forces 11B2S, later 18B, weapons man. (Also served in intelligence and operations jobs in SF).

The TSA Excels Again.. at Power Tripping

This is an old report, but the title is always true.

We all know the basic readout on the TSA: No one good, decent, honest, competent, moral, ethical or intelligent has ever been employed at the TSA in any capacity whatsoever.

And we haven’t had much to say about them since they walked a bunch of imams affiliated with the Moslem Brotherhood and other pro-terrorist groups through their procedures back in August.

You know what that means, right? It’s time to clear the TSA spindle.

Item: Texas Group Grope

Here’s a story from DFW, where mom of a special-needs kid, Jennifer Wilson, posted, as reported in the Fort Worth Star-Telegram:

We have been through hell this morning. They detained Aaron for well over an hour at DFW. (And deliberately kept us from our flight… we are now on an alternate) We were treated like dogs because I requested they attempt to screen him in other ways per TSA rules. He has SPD and I didn’t want my child given a pat down like this. Let me make something else crystal clear. He set off NO alarms….

I wish I had taped the entire interchange because it was horrifying. Somehow these power tripping TSA agents who are traumatizing children and doing whatever they feel like without any cause, need to be reined in.

Good luck with that. They’re untouchable, and you must not Question Their Authoritah.

Mrs Wilson said she was held for “over and hour” so the TSA group could grope her kid. The TSA’s six-figure PR officials, as competent as the rest of the agency, countered with “35 minutes.” The spokesman later admitted that was a lie, but now wants the public to believe “45 minutes.”

In case you ever wondered what happened to Joe Isuzu, the answer seems evident.

Item, 2016: Gross Mismanagement

In front of Congress last year, TSA workers complained about “gross mismanagement.” And they said that “more turnover is needed.” Since then, the TSA has turned over whistleblowers, not the mismanagers.

Item 2016: Over $70 Billion had been wasted on the TSA by this time last year, including $1B on the failed “Behavioral Detection Officer” program. This doesn’t cost the economic cost of the time Americans waste waiting on TSA, estimated in the same article as an additional $8 Billion. More people have actually died driving to avoid the TSA gropers than died on 9/11, given the greater per-mile death hazard of driving over flying.

Item Aug 16: TSA Cracks Down on Batarangs

Only the payroll patriots of the TSA can fight the fans of the masked man who fights crime. Or something.

The TSA has priorities, and one of them is making sure that the attendees of comic conventions don’t get their novelties home. TSA’s six-figure overpaid PR flacks:

Passengers are not allowed to bring anything on a plane that resembles a weapon, so anything like a boomerang or anything like that would not be permitted in the airplane cabin.

And

Every year during Comic-Con International, our officers have issues with the various items that people purchase and then either carry-on or place in their checked bags. These come in the form of figurines, costume items (including replica and real weapons) and other mementos that generally alarm our checkpoint and checked baggage screening systems and result in a bag check.

In other words, “We’re too stupid to tell toys from weapons.”

But maybe they’re on to something. Right around the same time, some nutball threw one at a police cruiser. Of course, that was in ever-weird Seattle. The cruiser, as you might expect for a steel thing that had a toy thrown at it, was unharmed.

Lord love a duck.

Item, Feb 2017: “Wave of Security Lapses”

A series of reports on leaked security documents from Stewart International (a reliever airport northwest of New York City) demonstrate both TSA overreach (on an airport that sees only occasional flights) and that TSA’s overreach vastly exceeds its grasp. One of the things it dropped the ball on was checking pax against the no-fly list.

Item, Feb 2017: TSA’s Legacy of Failure

As TSA waits for a new political-appointee director, a news story recounts the agency’s immediate history: nothing but a litany of failures and misconduct, just that month:

  • On Monday, 11 people walked through a security lane at New York’s John F. Kennedy International Airport without being screened;
  • Last week, TSA employees were indicted for smuggling cocaine from Puerto Rico
  • Earlier this month, a House Homeland Security Committee report indicated the TSA failed to properly vet and screen potential employees, uncovering examples of “insider threats” within U.S. airports.

If you really want to see the entitled incompetence of TSA employees, read the comments to that story where one of them speaks up to prove that no one good, decent, honest, competent, moral, ethical or intelligent has ever been employed at the TSA in any capacity whatsoever.

Shorts (clearing a large spindle)

Conclusion: is it time to disband this thing yet?

A Translucent, .22 Glock?

That’s sure what this looks like:

Where did it come from?

There’s a clue in the pictures, and it’s clearer if you look at this shot of the bare frame…

…bare frames….

…rendering…

…and print in progress.

Yeah, it’s a 3D printed Glock. Cue the media meltdown now.

Yes, it does shoot:

*Update* Test firing the 3D printed Glock frame

Of the test fire, Matt, the maker, wrote:

First test of the frame. Fired prob 10 rounds through it. No issues found with it as of yet. …I was on a schedule and had to leave pretty quick so I ran my tests real quick to see how it looked then took off.

The frame does depend on metal rail inserts, and the designer has promised to release the .stl files… after a frame rail redesign.

Responding to skepticism about the part strength, he wrote:

It would take a long time for the actual frame to brake. Nylon is incredibly strong and specifically this nylon I am using is very close, property-wise, to the nylon Glock uses in their frames and they don’t tend to break very often even after hundreds of thousands of rounds. The first thing to go on my frame would be the rear metal rails since they are held in by a strong glue but have shallow slots since there is not a lot of room back there. I am redesigning the print a bit to allow me to actually put solid, connected rails into it mid print to help alleviate the need for glue since it will always be the first failure point. I am also modifying the design to add rear nylon rails along with the metal ones because the combo of nylon and metal on the front is proving to be very resilient and precise vs the only metal rails in the rear.

The material he’s using is Taulman Nylon 910.

…the easiest nylon I have ever worked with. I made the dehydrator they actually have on their site and that thing is amazingly good and cheap… then I just ran the nylon on the recommended settings and it was already pretty good then I just tweaked it a bit with calibration to get my printer zeroed in and that frame was printed with no issues at all, other than some minor warp when it cooled. And as a minimum 10 hour print it had a good amount of time to mess up.

He explains that the Nylon solves the single greatest bugbear of highly-stressed 3DP Fused Filament Fabrication parts, layer stratification and delamination:

Normally, yes, 3D printed would have a weakness in the layer adhesion. Nylon specifically though has incredibly good layer adhesion when printed properly. The times I have managed to break nylon parts they have never delaminated and always broke across laminations randomly. It is pretty much the way even an injection molded nylon part would break.

He’s not done:

The next iteration of the frame will be even better and will have an even longer potential life with no need for repair. I have identified a couple places that end up being a pain when its printed but don’t matter as much when injection molded, so I am working around them to make it specifically a solid 3D printable frame. I also have a few ideas for alternate frames based on the pistols in mass effect.

For more information:

 

Walking in PO Ackley’s Footsteps

In a post we wrote a couple of years ago but that never appeared on this blog (because it was never finished), we wrote about legendary 20th Century riflesmith and cartridge wildcatter Parker Otto Ackley, known to all as P.O. Ackley.

PO Ackley made an entire career of making what he called “improved” cartridges. Each of the Ackley improved cartridges was based on some mainstream cartridge but with an increased powder capacity and a sharper shoulder, which implies less taper in the body of the cartridge itself.

We described Ackley similarly in another post that did get published, in 2012. That of course understates Ackley’s career, because apart from all his cartridge wizardry, Ackley was a gunsmith, barrel maker, and a writer with a prodigious capacity for work.

in a new book by Fred Zeglin, this career is explored and evaluated, and Zeglin actually emulates some of Ackley’s famous experiments, including these on Bolt Thrust that are excerpted at GunDigest.com.

Since the post-WWII years, if not before, there has been an ongoing argument concerning whether breech thrust (bolt thrust) is reduced by the improved case design. P.O. Ackley has certainly influenced the argument. The definition of an improved case is pretty simple. The case body is blown out to minimum body taper, which is described by Ackley as 0.0075 per inch taper. Shoulder angles between 28 and 45 degrees are normally considered to be improved, although it could be argued that any shoulder sharper than the original parent case is improved. Finally, an improved design allows the firing of a factory cartridge in order to fireform the brass for the new design.

…a method of recording breech trust was necessary in order to go beyond the somewhat subjective experiments that P.O. Ackley wrote about in Handbook for Shooters and Reloaders Vol. I. There Ackley used a Model 94 Winchester because, as he stated, “We often hear that the Winchester Model 1894 action was designed for low pressures and is an action which could be described as ‘weak.’” The purpose of his experiment with the ‘94 was to prove that the improved case design minimized bolt thrust; that the brass will support and contain some pressure; that oily chambers increase bolt thrust; and finally, the notion that actions are designed for specific pressure ranges is a fallacy.

Zeglin conducted a high-tech version of Ackley’s tests, using a test fixture he developed, “a .30 caliber barrel with a universal breech plug to allow for adjustable headspace, and to accommodate the strain gauge utilized by the Pressure Trace.” He developed loads beyond the SAAMI pressure limit for the .30-30 Improved, and discovered that even with excess headspace, the Improved case stayed in place, extruding the primer instead of shearing its head off. Conclusions:

[W]as Ackley right about his findings?
Yes, but he may have missed a point or two.

Since .30-30 brass is thick and pressures are low relative to brass strength and case capacity, with most appropriate powders pressure is not a big problem. To be fair, we did find some powders that will develop pressure far beyond SAAMI levels for the .30-30 AI case. Because the brass is so thick, it actually cannot stretch and cause head separations due to excess headspace. In that respect the .30-30 is not a good choice for Ackley to prove that improved designs handle pressure better.

However, Ackley used the .30-30 because the ‘94 Winchester action had been labeled weak. In this respect, Ackley did prove that the ‘94 can handle anything the .30-30 or .30-30 AI can dish out, without any question.

Bear in mind that the action of the Winchester ’94 was labeled weak by Winchester, who wanted to upsell customers to stronger rifles, like the ’95, which could handle the big-game and service cartridges of the early 20th Century with no problems.

There’s quite bit more to it, so Read The Whole Thing™. In other things in the book there is something that made us order it: Ackley’s own, previously unpublished, description of his own home-made cut rifling machine. (See the Table of Contents left).

Like any highly specialized book, it’s expensive, and has potential to go out of print at some time in the future. That’s just life in specialty book markets.

How expensive? The list price for hardcover or eBook is $60, although at this writing Gun Digest is sweetening the deal with $10 off the hardcover edition, and free shipping. (Pity they don’t offer a deal on both. We prefer hardcover books, but you can take a Kindle or iPad into the shop without worrying about getting cutting fluid on an irreplaceable heirloom). For what it’s worth, we just ordered the hardcover.

While this book rates the full price (to us at least), Gun Digest publishing does find itself overstocked from time to time, and if you’re into gun books and willing to let price be your guide, they have Under $30 and Under $15 pages, too. Free shipping if you can run the tab to $50 — we bet you can. (Dunno what the shipping is to those of you dwelling in foreign lands).

When Guns are Outlawed, Only Outlaws will have Sharp Turns

Three years ago, a sharp turn — and, perhaps, the usual Korean slapdash engineering and systems operation — caused an intercity ferry to roll. All ships roll in turns, but Sewol kept rolling, and sort-of-stabilized with a profound list… that guaranteed flooding, more list, and the vessel turning semi-turtle and slipping beneath the waves.

The crew did not cover themselves with glory, or even live up to the ancient honor code of the seaman. They saved themselves, or froze, disbelieving, in place. They ordered the passengers to return to their cabins and await rescue.

Rescue wasn’t coming.

The Republic of Korea did not have sufficient SAR resources for the conditions — naturally, it was dark, and the weather foul — or the sheer number of passengers. Few nations’ coast guards or lifesaving services would; they’re great at lifting a family of four from a dismasted yacht, or plucking the 8-man crew of a modern merchant ship from the sea, but hundreds of people would overwhelm anybody, and the ROKs’ lifesaving resources were overwhelmed.

Over 300 souls, most of them passengers, most of them children on a school trip, were extinguished.

This week, the ship was raised… to renew a disappointingly incomplete investigation (which so far has settled blame on the captain, who most certainly did not go down with his ship, and who has been threatened with the death penalty), and in hopes of recovering the remains of nine who are still missing.

The ferry, Sewol, was structurally unsound, overloaded and travelling too fast on a turn when it capsized and sank during a routine voyage off the southwest coast on April 16, 2014.

Bereaved families have been calling for the ship to be raised and for a more thorough investigation into the disaster. Officials also hope to find the last nine missing bodies.

Salvagers started to bring up the vessel, which has been lying on its side at a depth of 144 feet, late on Wednesday, and worked through the night.

Television pictures taken from the air early on Thursday showed the white 460-feet long hull, coated in mud and sediment, breaking above the surface, flanked by winching barges.

“The work needs to be done very cautiously,” Lee Cheol-jo, an official at the Ministry of Ocean and Fisheries, which is in charge of the operation, told a briefing.

It’s a hell of a thing, both that this is necessary, and that it is possible. A Clive Cussler tale come to life, but with no lost treasure or happy ending. And consider this:

A Chinese salvage company has fitted 33 beams beneath the hull with 66 hydraulic jacks inching the ship up.

via Sewol ferry raised in South Korea after THREE years | World | News | Express.co.uk.

There was a time that your go-to guys for marine salvage would have been British or Dutch. Then, there was a time where the know-how rested unquestionably in American firms.

Now, if you want to raise a ship from the depths and solve a mystery, you look to China. (We can barely build warships, any more, and no US merchant ship is ever built except for some government boondoggle). The raising of Sewol is a true extreme-engineering case, and her Chinese salvors are to be congratulated. (Not that they’re done yet, but they’re on track for mission completion).

There’s a lot to be learned from this accident, but we wonder if the highly politicized environment in the Republic of Korea is conducive to such learning. In our experience, only disinterested and professional investigators have any real hope of getting to the bottom (no pun intended) of such a complex accident. Adversarial proceedings and public hearings are almost certain to be useless, at least in terms of understanding what happened, and preventing next time.

Thereby guaranteeing a next time.

Plus de Napoleon — Invasion of Russia

The last historical film we presented on Napoleon chronicled his rise, which was built largely on good fortune and pure nerve. Those continued to serve him in good stead, amplifying his self-regard, up until his rather irrational decision to solve Russian backsliding on alliance with him… by invading Russia, in 1812. (With Bonaparte so preoccupied in the East, Britain was able to take a decent shot at turning a war they stumbled into, into a near-run reconquest of America … but that’s another story). This French film (professionally dubbed into rosbif) is a more traditional documentary, with acted scenes separated by low-budget CGI and talking-head historians (both French and Russian ones, who have a somewhat different view). The first half of the video culminates in Napoleon’s pyrrhic victory at Borodino before Moscow. A much weakened Grande Armée then takes up lodgings in an empty Moscow… that is promptly set afire by clandestine incendiaries, sent out by Alexander I. At this point, Napoleon’s plan, to defeat the Russians and impress them into alliance, is absolutely impossible. He persists.

Here’s the second part, in case the first one doesn’t lead in automagically.

It does underestimate the now-proven effect that disease, especially typhus, had on the Grande Armee. Instead, they attribute the devastation of the army to stress and starvation.

Napoleon made several errors here:

  1. He underestimated his opponent;
  2. He underestimated the effect that disease, especially typhus, would have on the Grande Armee; 
  3. He conducted a total war with limited-war aims;
  4. He believed that a single decisive victory would end the war on his terms.
  5. When he took the enemy’s capital, he considered himself the victor, and the campaign over. To his chagrin, the Russians didn’t see it that way.
  6. When it was clear his plan had no hope, he clung grimly to it.
  7. When he finally made the call to retreat from Moscow, he made it far too late for a horse-drawn army — 19 October 1812.

Every one of those errors comes, in our opinion, from his charmed life that began when he made gambles against tall odds, and seemed charmed to win, regardless of those odds. Improbability obeys mathematical laws and cannot continue forever, even if Napoleon hadn’t been stacking the wagers on his gambles ever higher.

The biggest casualty of the ill-considered Russian Campaign may have been Napoleon’s aura of invincibility.

Tons of Details on German WWII MG Tripods: “Lafettes”

We can’t discuss machine guns on this site without someone — usually Kirk — reminding us that the GI M122 tripod is rudimentary junk, and the class of the tripod world was the German Lafette 42. We’d like to steer those interested in these ‘pods to the incredible Lafette 34/42 web page of “Bergflak (“Mountain AA”) who is posting his work in progress on these amazing feats of German engineering.

How complicated was it? These are the parts of the lower half of the MG.34 Lafette. (The lower half of the MG.42 version was fundamentally identical).

Not complicated enough for you? Here’s 100-odd more parts from the Oberlafette, or upper half.

But wait, there’s more! 70-something parts that comprise the T&E mechanism.

Here’s a brief blurb from Bergflak:

The MG Lafette was a pretty complicated piece of machinery for its time. Some would say “typical German over-engineering”. It contains several systems that all work together. The difference between the Lafette 34 and the Lafette 42 is mainly the cradle. The weapon mounts and the trigger mechanism are simpler on the MG42 cradle. In addition it has a different bolt box. Everything else seems to be identical.  This page will only describe the Lafette 34. The change from the Lafette 34 to the Lafette 42 will be fully dealt with on the Wartime development page. On this page I will briefly explain the function of each of the components that make up the Lafette. For an even better and deeper understanding of the components you must visit my page Extreme details or the pages about Evolution of the Lafette (when they are finished).

via MG34 Lafette construction and details.

These pages explain which each part does, and pages on the evolution of the MG-34 and MG-42 Lafettes actually are complete now. Unfortunately, the page explaining the usage and employment of these tripods is not yet complete.

The whole site is worth reading already, and it stands to reason that as more information is acquired and analyzed, the site will just keep getting better and more useful.

Sunday Storytelling

There’s a million stories in the naked city, or something like that. There’s only a few stories a day at WeaponsMan.com, and a lot of them are pretty dry if you’re not a gun person. Here’s a few updated on stories that have been told before:

  • Tom Kratman has reappeared in the comments after a long absence. We believe that’s an indicator that he may have just dropped a manuscript on his editor and is in the calm before publication, but perhaps he has other reasons. Meanwhile, Tom and Amazon are offering you the Crack Dealer Special: your first hit of the Carrera SeriesA Desert Called Peace, for free (on Kindle). The series was great entertainment even paid for. Some people have charged that Carerra is a Mary Sue: he’s just like Kratman only more so: more handsome, more accomplished, more lucky, and more sociopathic. All we will say to that is that Tom would not center a series on a character who was unbalanced for no reason.
  • We mentioned before that even though most “hate crimes” are hoaxes, and most “nazi threats” are as dead as Adolf his crazy old self, there are real neo-nazi murders; even if they’re very sparse compared to the TV version, they actually do occur in non-zero quantities worldwide. And even though TV has 1000 white racists killing black people to 0 black racists killing white people, in the real world the situation isn’t entirely reversed: while whites killed out of black racism and resentment are an everyday affair, there is a non-zero set of real white racists who kill black people. A pox on all of them. (Worse yet, this asshat was a veteran. May his poxes contract poxes).

While the happy news readers on TV are often lying (the tell is: their lips move), the mystery of man’s bestiality to man, and the sheer complexity of the human race, makes life imitate their art, occasionally.

In cheerier news, the Official Blog Niece has distinguished herself in dance competition yet again, and the weather is warm enough for Small Dog Mk.II to enjoy some outdoor time, which is his favorite. (That’s the thing with dogs: everything is their favorite).

And we’re looking forward to a great week in the Extended New England Winter.

When Guns are Outlawed, Only Outlaws will have a Tea Break

Ah, those Englishmen. Gotta have their tea, even if they just got a call “See the woman, possible suicide.”

After the wild tea parties were over, the woman was found.

Dead.

Worse, the tea came from that suspicious Colonial tea vendor, Mickey D’s. What manner of Londoners were these strange rozzers?

Two police officers who went to McDonald’s to buy a cup of tea before responding to a suicide call have been allowed to keep their jobs.

Well, you really don’t want to have the tea after the call, do you? (And especially the biscuits… especially after some of the riper suicides).

PC Gavin Bateman and Tony Stephenson had received a call, graded ‘significant’ by the Met, shortly after midnight on April 16.

But rather than head straight to the home of a woman in Poplar, east London, deemed vulnerable by the London Ambulance Service, they waited 24 minutes before heading there.

Instead, the pair drove to the local fast food restaurant to pick up some refreshments and complete ‘administrative tasks’ before continuing with the call, a misconduct panel heard.

But by the time they reached the woman’s house, almost 40 minutes after a friend had called 999 when she received a suicidal text from the woman, the 22-year-old was found dead.

Yet today a Metropolitan Police disciplinary hearing gave the two police officers written warnings after they admitted misconduct but denied gross misconduct.

Amy Clarke, representing the Met, told the hearing: ‘The call was graded ‘S’, meaning significant, the more significant grading is ‘I’ which means the officer has to attend immediately.

‘PC Stephenson confirmed to the contact centre that they had accepted that call and that they were en route, that was at 00.03.

‘The CAD (dispatch system) went through to the vehicle so the officers could read the details which said ‘police requested for psychotic illness, significant risk to herself or others.

OK, so we get this deep in the story before we learn the two accused cops weren’t told it was an explicit suicide threat, but rather that it was a Crazy Lady call.

Anyone who has ever dealt with a Crazy Lady, copper or not, ought to know that fortifying oneself with the caffeinated beverage of choice beforehand is probably a good idea, and in most cases you will be facing an unpleasant but not life-consequential experience.

‘The officers decided not to proceed straight to the address and went to a nearby McDonald’s where they purchased refreshments before driving to a roundabout where they drank their drinks.

‘At 12.37 the officer’s left and went to [the woman’s] address.

via Police officers stopped at McDonald’s instead of helping suicidal woman | Metro News.

Let’s not lose sight of the fact that the officers didn’t kill her. Loon killed her self. It is quite difficult to keep a determined suicide from whacking him- or herself; it’s still worth trying, but the failure here is not the officers’. We think the verdict of “negligence deserving reprimand, not gross neg demanding firing” is just about right.

One last thing: if you get a text from a suicidal friend, maybe you’d better not count on Teh Authoritah to go to the friend’s aid.

Thanks Ever So Much… Jody

Consider the important part played in national defense by one often forgotten individual — Jody.

If you served, Jody needs no introduction. He’s the civilian guy who’s got your girl and gone while you were away at the drill faces (pun intended) of the salt mines. If you didn’t know, “Jody” is the much-reviled star of dozens of cadence calls, used to get trainees’ brain stems into sync so that they march in step, and their minds lose any grip on the fact that D&C is training for any of the wars of the eighteenth century.

But that’s the Army for you: centuries of tradition, untainted by progress.

Jody serves a valuable purpose, as hard as that is to bear in mind when you’re trying to talk PV2 Joe Tentpeg into putting down the .45 because Mary Sue Rottencrotch back on the block is not really worth particle-blasting the inside of one’s cranium with gunpowder over.

First, Jody polices up all the untended Mary Sues, keeping the dating market in balance back in Hometown, USA, when the boys run off and join up. He prevents them from suffering the girlish feelings that proceed from separation and loss, and gets them started on the womanly emotions that attend duplicity and backstabbing.

He also provides a great motivator than training NCOs can exploit to keep young soldiers and junior officers in a razor’s-edge state of fighting keenness.

These are some of the reasons that some unknown philanthropist has chosen to honor Jody with his first-ever motivational bumper sticker:

Consider one of Jody’s other accomplishments: he also peels off many unsatisfactory and unworthy former girlfriends and ex-wives, letting soldiers seek superior women, more suited to their higher status.

For all these reasons, considering what-all he’s done for the boys, why, Jody’s practically a veteran himself, by now.

He could even have PTSD from a decade of listening to Mary Sue complain.

And deep down inside, every soldier knows it: Jody? Sucks to be him.

Slo-Mo Mayhem

We’re not really feeling it for a technical post this morning, so instead let’s introduce Andrew, a self-described “gun nut” and the personable host of the one-year-old GY6 Slo Mo video channel. Here is a loooong burst with a gun that solves a problem nobody has, a belt-fed full-auto AR in 9 x 19 mm.

This isn’t especially practical. If there’s something that needs a whole belt of 9mm at point-blank range, you fight it, we’re backing off and calling a fire mission. But it looks like fun and that’s reason enough to own a gun.

Actually, if you are interested in the Freedom Arms FM-9 belt-fed upper, he has a 20 minute full review, that answers pretty well “what it is,” without going deep into “what it’s for.” The quick-change barrel system (enabled by the gun being a simple mass-locked blowback) is clever and good.

We don’t think we want one, but we do think we understand it after Andrew’s video.

The feed mechanism is the now-customary MG-42 based design. Our guess, without examining the weapon, is that the reason that Freedom Ordnance wants you to load the belt with the feed tray cover down, and not up (mentioned at about 6:45 and 8:45), is because closing the feed tray with the bolt forward can damage the mechanism. It’s possible to design a feed system that can be safely close bolt-forward or -back — FN’s world-market machine guns are designed that way, by having a spring-loaded roller. 

And here’s the promised first of a series of ballistic videos.

These videos are quite unscientific, but they’re entertaining. Entertainment is an interesting use for high-speed photography that was developed for scientific and industrial purposes. (And, he makes it clear, he’s not trying to be scientific).

Don’t expect any great revelations from the shot-in-the-head videos. A 9mm kills Casualty Carl dead. Supersonic rifle rounds will usually produce an avulsed (evulsed?) cerebrum in Homo sapiens and will probably result in the catastrophic structural failure of Casualty Carl’s coconut skull… killing him dead. A .22 LR from a pocket pistol will break up the skull less, but will probably still kill Casualty Carl dead. In real life, humans have survived and recovered (more or less) from gruesome, close-range cranial wounds with all these weapons, but the odds are a head shot that’s a square hit has taken the recipient out of the fight for the immediate future.

Hat tip, The Gun Feed.