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Bolt Actions
Bolt-action is a type of manual firearm action that is operated by ''directly'' manipulating the bolt via a bolt handle, which is most commonly placed on the right-hand side of the weapon (as most users are right-handed). Most bolt-action firearms use a rotating bolt design, where the handle must first be rotated upward to unlock the bolt from the receiver, then pulled back to open the breech and allowing any spent cartridge case to be extracted and ejected. This also cocks the striker within the bolt (either on opening or closing of the bolt depending on the gun design) and engages it against the sear. When the bolt is returned to the forward position, a new cartridge (if available) is pushed out of the magazine and into the barrel chamber, and finally the breech is closed tight by rotating the handle down so the bolt head relocks on the receiver. Bolt-action firearms are generally repeating firearms, but some single-shot breechloaders also use bolt-action design ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Breechloader
A breechloader is a firearm in which the user loads the ammunition (cartridge or shell) via the rear (breech) end of its barrel, as opposed to a muzzleloader, which loads ammunition via the front ( muzzle). Modern firearms are generally breech-loading – except for replicas of vintage weapons. Early firearms before the mid-19th century were almost entirely muzzle-loading. Mortars and the Russian GP-25 grenade launcher are the only muzzleloaders remaining in frequent modern usage. However, referring to a weapon specifically as breech loading is mostly limited to single-shot or otherwise non-repeating firearms, such as double-barreled shotguns. Breech-loading provides the advantage of reduced reloading time, because it is far quicker to load the projectile and propellant into the chamber of a gun/cannon than to reach all the way over to the front end to load ammunition and then push them back down a long tube – especially when the projectile fits tightly and the tub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Nikolaus Von Dreyse
Johann Nicolaus von Dreyse (20 November 1787 – 9 December 1867) was a German firearms inventor and manufacturer. He is most famous for submitting the Dreyse needle gun in 1836 to the Prussian army, which was adopted for service in December 1840 as the ''Leichte Perkussions-Gewehr M 1841'' – a name deliberately chosen to mislead about the rifle's mechanism – later renamed Zündnadelgewehr M 1841 in 1855. Biography Dreyse was born in Sömmerda (then ruled by the Archbishopric of Mainz), the son of a locksmith. Dreyse worked from 1809 to 1814 in the Parisian gun factory of Jean-Samuel Pauly, a Swiss who designed several experimental breech-loading military rifles. After returning to Sömmerda in 1824, he founded a company to manufacture percussion caps. It was there that he designed the needle rifle. While the gun is thought of by some to be the first bolt-action rifle, in reality it bears little resemblance to modern bolt-action rifles, except for the bolt principle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accuracy And Precision
Accuracy and precision are two measures of ''observational error''. ''Accuracy'' is how close a given set of measurements ( observations or readings) are to their ''true value'', while ''precision'' is how close the measurements are to each other. In other words, ''precision'' is a description of '' random errors'', a measure of statistical variability. ''Accuracy'' has two definitions: # More commonly, it is a description of only '' systematic errors'', a measure of statistical bias of a given measure of central tendency; low accuracy causes a difference between a result and a true value; ISO calls this ''trueness''. # Alternatively, ISO defines accuracy as describing a combination of both types of observational error (random and systematic), so high accuracy requires both high precision and high trueness. In the first, more common definition of "accuracy" above, the concept is independent of "precision", so a particular set of data can be said to be accurate, precise, both, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
