Wikipedia:Reference desk/Archives/Science/2018 April 27

= April 27 =

Why aren't 3/8 inch and 1/4 inch common calibers?
But .38, .357 and c. .22 are. Decimal inches are less common than fractions of inches in most non-gun fields so why not? Sagittarian Milky Way (talk) 01:46, 27 April 2018 (UTC)
 * Although the article Caliber and especially the article .357 Magnum don't quite come out and say it explicitly, it seems like specific calibers were derived experimentally, for specific usages. ←Baseball Bugs What's up, Doc? carrots→ 03:36, 27 April 2018 (UTC)
 * .25 ACP 251/1000" was introduced in 1906 (patented 1905). .25 NAA 251/1000" was introduced in 2002. .380 Revolver Short and .380 Revolver Long 3/8" were introduced in 1860s. .375 Winchester 3/8" was introduced in 1978. Sleigh (talk) 12:26, 27 April 2018 (UTC)


 * It is instructive to think about how these items are manufactured - and how they were historically manufactured. Firearms, and their ammunition, are one of the oldest artifacts that were built using machine tools and their manufacture was intricately linked to other developments of the industrial revolution.  Modern commercial ecosystems carry a lot of the historical "inertia" - so even though today we may use CNC mills and robotic metal machines, we have a lot of backward compatibility to consider.  (Vis: 2017 Annual Statistical Update from the ATF).
 * If we're building barrels using a CNC router - or if we're using computer simulations to study ballistic physics - then typing in a simple fraction or a simple decimal makes that part of the work easier.
 * But if it's 1855 and we're using a metal gauge to control the mill, it makes no difference whatsoever if the gauge is a nice rational number, or some part-of-an-inch or part-of-a-furlong-whose-value-cannot-be-expressible-using-conventional-algebras. Your manufacturer would just slide the metalworking tool down to the gauge and mill that much.  The result is a perfect, reproducible, accurate, standardized metal piece, whose precise dimensions expressed in inches are irrelevant for many purposes.
 * If you spend two hundred years building armament in that fashion, then by the time you invent the precision CNC mill, you have to type in whatever inconvenient number is compatible with the billions and billions of bullets that are already on the marketplace, and your product has to be compatible with the stuff built by hundreds of thousands of other people who are building ammunition. Millions of people aren't going to change their way of life just because it'd be great if everyone wised up about simple facts!
 * Many times before, I have cited James Burke's excellent and very old history documentary series, Connections (1978). In several episodes - particularly, Episode 5 (40 minutes in), there is a great analysis of the interplay between proto-industrial manufacturing and tooling, and the embodiment of those historical technological conventions into the shape of modern artifacts.  Half of that episode is about the significant transition from musket to rifle, and why this minor detail of technology is so significant to the culture and history of the United States. (To wit: the Rifleman's Creed is not a general confession of adoration for firearms at large, but of rifles in specific; the first shots of the war that founded our nation are conventionally attributed to precision home-made rifles, rather than muskets - though historians naturally quibble about the important details; and of course, the Americans were the first to prove that rifles could kill other Americans really effectively).  In fact, historians call this transition of technologies, which irreversibly guided the course of the Industrial Revolution, the "American system of manufacturing" - in true form, largely guided by American innovation and our desire to build lots and lots and lots of guns.
 * The point - if there is any - is that precision in manufacturing does not specifically require a convenient numerical representation; and, if history gives us any wisdom, we can predict that people are going to keep doing the same old thing, for many more years.
 * Nimur (talk) 17:12, 27 April 2018 (UTC)


 * Very informative, I learned a lot from that. Maybe if the sweet spot for rayguns turns out to be 1.007cm +/-14% the 11.43mm rayguns will outsell the 1 centimeters for decades after the boxes only say metric.. Sagittarian Milky Way (talk) 03:58, 30 April 2018 (UTC)


 * Agree with User:Nimur, but the British Brown Bess musket had a internal barrel diameter of 0.75 (¾) inch, which required a ball diameter of 0.69 inch to stop it getting stuck inside. From there, we went to the 0.45 inch Martini–Henry rifle. So it seems that there has been a move away from nice round figures, perhaps because of the increasing complexity of the variables. Alansplodge (talk) 11:27, 28 April 2018 (UTC)

Has the 75% loss of flying insect mass been observed outside of Germany?
Ref.: 174.16.98.178 (talk) 20:00, 27 April 2018 (UTC)
 * It was observed in England. Ruslik_ Zero 08:02, 28 April 2018 (UTC)
 * Citation needed User:Ruslik0? The 75% figure was from a study of nature reserves in Germany. A study by Rothamsted Research comparing insect traps in England between 1970 and 2000 found no decrease in weight of insects in some areas, but a 60% reduction in Herefordshire.  Alansplodge (talk) 16:23, 28 April 2018 (UTC)


 * Insects are gone, the birds that eat them are gone also, fruit plants are not pollinated. A wonderful consequence of progress and development. AboutFace 22 (talk) 21:07, 28 April 2018 (UTC)