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Monday, October 29, 2018

October 29, 2018 -- A Quick Run Around The Web

"Hipster Hotness: 6.5mm Grendel Hornady Custom 123gr SST Gel Test"--AR15.com (5 min.)
Note that the test is being conducted from a 12-inch barrel. Alexander Arms, which developed the cartridge, recommends a 20-inch or 24-inch barrel for hunting. Muzzle velocity out of the 12-inch barrel was 2,287 fps. Turning to some ballistic tables produced by Alexander Arms (PDF) which has velocities for 123 gr. SST rounds, this is equivalent to the velocity between 50 and 100 yards from a 19.5-inch barrel, and between 100 and 150 yards from a 24-inch barrel. 

I had every bit of confidence in the gun, the load, and the scope. I’d been told all week that 500 yards should be easy. But as my finger settled on the trigger, the gun moved, imperceptibly on my end, but 480 yards away, it caused the reticle to jump from the buck’s lungs to the backstrap to the guts and back again. I hesitated and thought to myself, This is too damn far. Seconds later, the buck vanished.
  • "Small Pistols Have Some Inherent Problems"--Active Response Training. Besides being more difficult to shoot accurately, they are more difficult or impossible to manage one handed malfunction clearance. Some pistols lack any rear sight at all, let alone one that allows for one handed racking of the slide; others lack a manual slide lock. Which brings me back to a point I've made before when someone raises the problems with small auto-loaders: if it worries you, just get a revolver.
  • "Why Put Your Windows Down?"--Schafer's Self-Defense Corner. Someone asked the author why, when shooting breaks out, experienced operators roll down their vehicle windows. There are several reasons outlined, but it essentially comes down to two factors: either you will be shooting out of the vehicle, so rolling down the windows help mitigate against hearing damage and allows you to shoot without having to shoot through a window; or you will be shot at, in which case the window down helps mitigate against a window shattering and spraying you with broken glass.
  • "How the Gun Control Act of 1968 Changed America’s Approach to Firearms—And What People Get Wrong About That History"--Time Magazine. Don't expect an unbiased article. Nevertheless it provides some of the historical context to passage of the 1968 Act. The article relates:
Though the 1968 law was a victory of sorts for gun-control activists, many were disappointed it didn’t include a registry of firearms or federal licensing requirements for gun owners. TIME reported [at the time], “It may take another act of horror to push really effective gun curbs through Congress.”
The final draft also didn't include the gun-controller's biggest goal, which was to ban handguns, although that was the original purpose of the legislation. The article also reports that the president of the NRA at the time stated that the NRA could live with the law and that it was reasonable. This made a lot of gun-owners realize that the NRA was out of touch with its base, and let to the 1977 NRA convention upset that saw some of the old-guard "play-along to get-along" thrown out of leadership positions to make room for those that were more willing to defend gun rights. 
  • "7.62 NATO vs .308 Winchester Ammo, What’s The Difference?"--Ammo Land. Most of these points I was already aware of: the different pressures, slight differences in chamber dimensions, and differences in the case wall thickness. The author says that the pressure difference is exaggerated, explaining:
That 50,000 number [for military ammunition] is actually an accurate representation of copper units of pressure or CUP. A far less precise way to measure pressure, the method literally relies on looking at how much little copper disks compress when you fire the gun. While there isn’t a consistent mathematical formula that equates CUP to pounds per square inch (PSI) across the board, the difference in this specific case is somewhere around 8,000. In other words, the maximum pressure for 7.62x51mm NATO is about 58,000 psi – not all that far from the 62,000 figure for commercial .308 Winchester.
    However, the difference in chamber size--in particular, headspace--should be considered:
             Military rifles for 7.62x51mm NATO can, and usually do, have longer chambers. In things like machine guns powered by ammo made all over the world, there’s got to be some slack for reliable feeding and operation with all that violence going on during the feeding and ejection process. The solution is to make the chamber headspace a bit longer. If you’re not familiar with headspace, think of it as the distance from the bolt face to the point in the chamber that stops forward motion of the cartridge case. If chamber headspace is too long for a cartridge, it will float back and forth in the chamber. If headspace is too small, the bolt will not close properly or will require excess force to close.
                How much different is the headspace? The .308 Winchester chamber headspace is between 1.630 and 1.6340 inches (SAAMI Info). The 7.62x51mm NATO is between 1.6355 and 1.6405 inches. While the published numbers show about six-thousandths of an inch difference, it’s not unusual for the headspace in a surplus 7.62 rifle to be 10 or even 15 thousandths longer than that of a commercial .308. That doesn’t sound like a big deal, right up to the point where you fire thinner commercial brass in a long-chambered rifle. The brass will stretch, possibly enough to contribute to a dangerous case rupture. Doing the same thing with thicker military brass is no big deal and the way the system was designed. Thicker brass can handle some extra stretching into a longer chamber throat, so it's no big deal.
          The author suggests using a set of Go/No-Go headspace gauges to spec your headspace before using commercial ammunition in your military rifle.

            "What they won't teach you in calculus"--3Blue1Brown (16-1/2 min.)
            Derivatives are generally pictured as the slope of a curve, but the author of this video discusses another way to think about derivatives. 

                       Upon hearing rumors of the caravan, the Salvadoran Ministry of Justice and Security dispatched police to patrol the perimeter of the plaza where migrants gathered Sunday morning, many with small backpacks and some with no belongings at all.
                        The measures were to ensure the safe passage of the migrants rather than hinder their journey, according to a ministry spokesman.
                         In a statement, Minister of Justice and Public Security Mauricio Landaverde emphasized that “mobility is a reality and a right.”
                  You read that correctly: a senior El Salvadoran officials claims that entry to the United States is a right.
                            All this nationalist populism is extremely threatening to the people who are arranging transnational institutions to benefit themselves. Everything you’ve been seeing in the gun issue lately fits that. Google censoring pro-gun views? Facebook doing the same? Big transnational companies like Levi’s donating large amounts to gun control? Financial institutions refusing to do business with gun makers, the NRA, etc? NRA not being able to obtain basic business insurance? That’s all been the people who control these transnational institutions attempting to put the brakes on populist sentiment using the institutional power they maintain control over. You didn’t see this happening a decade ago because a decade ago a lot of these institutions didn’t exist, or hadn’t cemented power. Facebook literally went from nothing, to a transnational corporation that can and possibly does decide national elections in 13 years. Think about that.
                            Very little is more threatening to an established order than the idea that they might be the targets of an armed revolt. Despite what many people think, it’s not because transnational elites want to kill you. ... What transnational elites want to maintain first and foremost is the acceptance and respect of other transnational elites who are like themselves.
                              In most countries, the established order can keep their thumb on the peasantry to maintain an order to their liking and still maintain respectability. ...
                               It’s a different story here. Our peasantry can complain: with guns and bullets. ...
                                  Whether some want to admit it or not, having an armed population is a significant check for minorities against the depredations of the majority. I’m not speaking only of racial or religious minorities necessarily here, though it’s true for them too. It goes back to the old quote from Al Capone: “You can get much farther with a kind word and a gun than you can with a kind word alone.” To the kind of people arranging the transnational order, this is the Worst Thing Ever. Not necessarily because it threatens their power in the immediate, but because it threatens their respectability with other people like them.
                                     Cliven Bundy and his family are still alive. Is there any reader out there who thinks Eric Holder couldn’t have given an order to ruthlessly crush the Bundys and anyone who came to their aid? Almost certainly he could have. Whether that would have set in motion a chain of events that would have escalated toward a much wider conflict I think is debatable, and I think it probably would have. But in the immediate, Holder could have wiped them out. There would have been bloodshed on both sides, but in the short term, Holder would have won. But he didn’t give that order. Why? Because he would have lost all respect from other transnational elites. Ruthlessly crushing rebellions isn’t a respectable business these days in those circles. That kind of thing might get you respect in Moscow, but not Davos.
                                        ... Capitalism created new forms of property ownership that divorced ownership from local communities. Even more critically, however, capitalism’s essential fact (per Schumpeter) is creative destruction. The old must be swept aside in order to create space for innovation. The process inevitably sweeps aside not just antiquated products but also traditions, ways of work, communities, and even human lives.
                                  This process is now so well accepted—even among many conservatives—that free market principles are presented “as ironclad laws about which we have no choice. Dwindling manufacturing jobs, technological displacement, global flows of labor and capital—we are told we have no alternative.” In such an environment, unregulated capitalism comes into conflict with those strains of conservatism that place paramount value on the permanent things.
                                    Also:
                                              The radical free market theories espoused by Friedman and his progeny, however, have not fared so well in recent decades, either at the policy or the theoretical level. They also make a poor fit for an increasingly populist conservative base. Of all the conservative strains, the populist ones have always been the most skeptical of free markets. They favor a vast array of policies abhorrent to libertarians, including limits on free trade and immigration and support for a strong government social safety network. In contrast, the constituency for libertarian free market policies is minuscule.
                                               Moreover, to the extent that free market capitalist theories have been given effect under American law, they have rarely served conservatism well. Conservatives have long valued a humane political economy, but the alliance between big business and the GOP has increasingly diminished the value of work in both the real economy and the moral economy. This is not to deny that capitalism (of various kinds—though certainly not always the libertarian kind) has produced great wealth and rising standards of living over recent centuries. It is simply to point out that the economy is now characterized by dramatic disparities in income and wealth, even while growth and productivity have been relatively low in recent decades. Although real earnings for most workers have stagnated, select portions of the new elites—especially in finance and technology—have profited beyond the dreams of avarice. And those elites who have benefited most from today’s market economy are increasingly unlikely to support conservative values.
                                          Controlling for divorce rates, religiosity, and socioeconomic status, he found that while 65 percent of women and 72 percent of men with one sexual partner in their lifetime reported being “very happy” with their marriage, that number drops to 60 and 64 percent, respectively, when adding even one other premarital sexual partner.  That number further drops with each additional sexual partner, until we get down to 55 and 59 percent satisfaction with one’s marriage above 10 sexual partners.
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                                          Weekend Reading -- A New Weekend Knowledge Dump

                                          Greg Ellifritz has posted a new Weekend Knowledge Dump at his Active Response Training blog . Before I discuss some of his links, I want to ...