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52-467: R93 may refer to: Blaser R93 , a German rifle Blaser R93 Tactical , a sniper rifle HMS  Vigilant  (R93) , a destroyer of the Royal Navy Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title R93 . If an internal link led you here, you may wish to change

104-426: A conical outer surface. The collet can be squeezed against a matching taper such that its inner surface contracts to a slightly smaller diameter, squeezing the tool or workpiece to hold it securely. Most often the collet is made of spring steel , with one or more kerf cuts along its length to allow it to expand and contract. This type of collet holds the external surface of the tool or workpiece being clamped. This

156-507: A hex key . Different bolt heads for different groups of calibers and magazine inserts are also user changeable, making the Blaser R93 a modular firearm capable of using a multitude of calibers in its chassis. A R93 Rimfire conversion kit was also available in .22 Long Rifle and .17 HMR consisting of a new magazine, barrel, bolt head and bolt catch insert. The rifle has a shorter overall length compare to more traditional designs due to

208-576: A 12.7 g (196 gr) projectile. In January 2004, 38-year-old German Albrecht Huf had an accident near Koblenz in Germany where his R93 chambered in .300 Weatherby Magnum exploded. Huf sustained injury to his thumb, jaw and zygomatic bone . He claimed to have used Weatherby factory ammunition only. An investigation by the German DEVA institute concluded that handloaded .300 Weatherby Magnum ammunition had been used that greatly exceeded

260-513: A Morse taper and can be removed to accommodate Morse taper drill bits . Morse taper collet sets usually employ ER collets in an adaptor to suit the Morse taper. The adaptor is threaded to be held in place with a drawbar . They can be used to hold strait-shanked tooling (drills and milling cutters) more securely and with better accuracy (less run-out ) than a chuck. On a wood router (a hand-held or table-mounted power tool used in woodworking ),

312-449: A clicking sound as if it had failed to fire, but exploded when he tried to pull the bolt back, which resulted in the bolt hitting his hand. The Swedish Blaser distributor later stated that while it is possible to pull the trigger without the bolt being fully locked into battery, the firing pin is designed such that it will not hit the primer with sufficient force to ignite the cartridge. Collet A collet / ˈ k ɒ l ɪ t /

364-453: A collar), this taper locks the retainer in place and the raised rib that sits in the circular groove on the valve stem also locks the collet halves in place to the valve stem. To remove the valves from a cylinder head a 'valve spring compressor' is used to compress the valve springs by exerting force on the spring retainer which allows the collets to be removed, when the compressor is removed, the retainer, spring and valve can then be removed from

416-444: A conjugate taper form. The taper geometry serves to translate a portion of the axial drawing force into a radial clamping force. When properly tightened, enough force is applied to securely clamp the workpiece or tool. The cap or drawbar threads act as a screw lever, and this leverage is compounded by the taper, such that a modest torque on the screw produces an enormous clamping force. The precise, symmetric form and rigid material of

468-501: A drawbar from behind, they are self releasing and tool changes can be automated. Unlike most other machine collet systems, 5C collets were developed primarily for work holding. Superficially similar to R8 collets, 5C collets have an external thread at the rear for drawing the collet closed and so work pieces may pass right through the collet and chuck (5C collets often also have an internal thread for workpiece locating). Collets are also available to hold square and hex stock. 5C collets have

520-408: A given collet holds any diameter ranging from its nominal size to its 1-mm-smaller collapsed size, and a full set of ER collets in nominal 1 mm steps fits any possible cylindrical diameter within the capacity of the series. With an ER fixture chuck, ER collets may also serve as workholding fixtures for small parts, in addition to their usual application as toolholders with spindle chucks. Although

572-466: A letter series of names) which Rego-Fix modified and appended "R" for "Rego-Fix". The series number is the opening diameter of the tapered receptacle, in millimetres. ER collets collapse to hold parts up to 1 mm smaller than the nominal collet internal size in most of the series (up to 2 mm smaller in ER-50, and 0.5 mm in smaller sizes) and are available in 1 mm or 0.5 mm steps. Thus

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624-539: A limited closing range, and so shank and collet diameters must be a close match. A number of other C-series collets (1C, 3C, 4C, 5C, 16C, 20C & 25C) with different holding ranges also exist. A collet system with capabilities similar to the 5C (originally a proprietary system of Hardinge ) is the 2J (originally a proprietary system of Sjogren, a competitor of Hardinge, and which Hardinge later assimilated). The SO Deckel tool grinders use these. Sometimes called U2 collets. Watchmaking at Waltham, Massachusetts led to

676-500: A metric standard, ER collets with internal inch sizes are widely available for convenient use of imperial sized tooling. The spring geometry of the ER collet is well-suited only to cylindrical parts, and not typically applied to square or hexagonal forms like 5C collets. "Autolock" collet chucks (Osbourn "Pozi-Lock" is a similar system) were designed to provide secure clamping of milling cutters with only hand tightening. They were developed in

728-831: A range of different size gear wheels. These, like straight rod-holding collets, close on the outer taper. Ring collets also come in sets of five and hold work from inside a hole. They open as they are tightened by an outside taper against the outer taper of the lathe headstock. Watch collets also include taper adapters and wax or cement chucks. These collets take an insert, usually brass, to which small parts are cemented, usually with shellac. The book The Modern Watchmaker's Lathe and How to Use it contains tables of makers and sizes; note that it refers to basic collets as split wire chucks . These collets are common especially on production machines, particularly European lathes with lever or automated closers. Unlike draw-in collets, they do not pull back to close, but are generally pushed forward, with

780-546: A recall on all R93 rifles sold in the United States, except the UIT, CISM, and LRS/LRS2 models, because non-stainless steel pins inadvertently had been used in some trigger units. Owners were urged to have their rifles inspected by Blaser's US representative to see if their trigger unit was affected, and if so be changed from a non-stainless to a stainless one. In 1994, after a shooting accident near Koblenz in Germany,

832-473: A round bar or tool, but there are collets for square, hexagonal, and other shapes. In addition to the outside-holding collets, there are collets used for holding a part on its inside surface so that it can be machined on the outside surface (similar to an expanding mandrel ). Furthermore, it is not uncommon for machinists to make a custom collet to hold any unusual size or shape of part. These are often called emergency collets ( e-collets ) or soft collets (from

884-557: A scope that switches on a red dot when the R93/R8 are cocked ("Zeiss Illumination Control/iC"). The iC system is based on the Zeiss rail . To avoid accidents with set triggers, Blaser offers the R93 only with a direct trigger, also known as single-stage triggers. The manual cocking system, or "de-cocking safety", enables the shooter to securely carry the weapon, only cocking the rifle just before

936-630: A shooting range near Bollnäs in Sweden, resulting in the bolt hitting his face. Svensson was using Norma factory ammunition. He turned in the rifle to Blaser, but wanted the Swedish National Forensic Centre to investigate the matter. However, he later agreed to the wish of Blaser and its Swedish distributors that all technical investigation would be performed by the German DEVA institute. The DEVA report concluded that

988-425: A split collet to hold both the inlet and exhaust valves under constant valve spring pressure which returns the valves to their closed position when the camshaft lobes are not in contact with the top of the valves. The two collet halves have an internal raised rib which locate into a circular groove near the top of each valve stem, the outer side of the collet halves are a taper fit into the spring retainer (also known as

1040-608: Is a list of some of the available factory chamberings for the R93. Several different barrel profiles were also available, such as Standard, Octagonal, Semi Weight, "Stutzen", Match or Safari Letters in parentheses corresponding stamping on the bolt head. The R93 was upgraded to the Blaser R8 introduced in 2008, which has a detachable box magazine/trigger combination. Production of complete R93 rifles ceased in 2016. The Blaser R8 displays an enlarged locking surface of 96 mm (0.149 in ) compared to 66 mm (0.102 in ) of

1092-410: Is a segmented sleeve, band or collar . One of the two radial surfaces of a collet is usually tapered (i.e a truncated cone) and the other is cylindrical. The term collet commonly refers to a type of chuck that uses collets to hold either a workpiece or a tool (such as a drill), but collets have other mechanical applications. An external collet is a sleeve with a cylindrical inner surface and

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1144-433: Is a truly modular system built around an aluminium alloy frame, offering differing stocks and barrels varying length and thickness available in chamberings from .22 LR to .375 H&H Magnum / .416 Remington Magnum / .458 Winchester Magnum size. It also came in caliber 28 (13.97 mm; 0.550 in) as a shotgun/slug barrel. The barrel has a quick-change design which lets the user switch barrels using two screws and

1196-489: Is difficult to keep the split collets in place whilst the compressor is released, by applying a small amount of grease to the internal side of the split collets will keep them in place on the valve stem whilst releasing the compressor, then as the spring retainer rises it locks the tapered split collets in place. The Blaser R93 (and related models) use a unique bolt locking system that employs an expanding collet. The collet has claw-like L-shaped segments that face outward from

1248-460: Is normally cylindrical, it can be made to accept any defined shape. Generally, a collet chuck , considered as a unit, consists of a tapered receiving sleeve (sometimes integral with the machine spindle), the collet proper (usually made of spring steel) which is inserted into the receiving sleeve, and (often) a cap that screws over the collet, clamping it via another taper. For machining operations, such as turning , chucks are commonly used to hold

1300-466: Is not clear whether the R93 Tactical variant is included in these numbers. The predecessor of the R93 was the 60 degree turn bolt action Blaser R84, which was discontinued after the introduction of the R93 in 1993. The successor of the R93, the Blaser R8 , was introduced in 2008. Production of the R93 ended by 2017, though Blaser continued to offer spare parts as stock allowed. The Blaser R93

1352-419: Is the 10 mm collet used by Clement and Levin. For work holding, collets are sized in 0.1 mm increments with the number on the face being the diameter in tenths of a millimetre. Thus a 5 is a 0.5 mm collet. Watchmaker collets come in additional configurations. There are step collets which step inward to hold gear wheels by the outer perimeter. These typically were made in sets of five to accommodate

1404-403: Is the most usual type of collet chuck. An external collet clamps against the internal surface or bore of a hollow cylinder. The collet's taper is internal and the collet expands when a corresponding taper is drawn or forced into the collet's internal taper. As a clamping device, collets are capable of producing a high clamping force and accurate alignment. While the clamping surface of a collet

1456-414: The workpiece . The table below gives a functional comparison of the three most common types of chuck used for holding workpieces. Collets have a narrow clamping range and a large number of collets are required to hold a given range of tools (such as drills ) or stock material. This gives the disadvantage of higher capital cost and makes them unsuitable for general usage in electric drills, etc. However,

1508-448: The 1940s by a now defunct UK company, Clarkson (Engineers) Limited, and are commonly known as Clarkson chucks. Autolock collets require cutters with threaded shank ends to screw into the collet itself. Any rotation of the cutter forces the collet against the collet cap taper which tightly clamps the cutter, the screw fitting also prevents any tendency of the cutter to pull out. Collets are only available in fixed sizes, imperial or metric, and

1560-575: The R93 in general do not fit the R8 series rifles, except for scope mounts. In 2000, a recall was announced on R93 rifles delivered with plastic bolt carriers. According to Blaser, only 0.4% of all R93 rifles had been delivered with plastic bolt carriers, and only on the R93 Offroad model. Due to the increased risk of accidents, Blaser offered to replace all such plastic bolt carriers with a regular aluminum bolt carrier for free. In May 2003, Blaser issued

1612-462: The R93 was criticised with claims that it could not withstand high pressures, and that the bolt would unlock when excessive pressures were generated. In August 2003, 41-year-old Norwegian Jan Sørlie had an accident where his R93 chambered for 8×68mm S exploded, resulting in loss of an eye and a skull fracture requiring titanium replacement. Sørlie reported that had used handloaded ammunition loaded with 5.05 g (77.9 gr) Norma MRP powder and

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1664-402: The R93. While the R93 collet has a locking angle of about 50 degrees, the angle of the R8 has been steepened to almost 90 degrees. Further the radial collet opens differently. This results in a less smooth operating bolt of the R8 when compared to the R93 series and some weight increase. Other differences are that the R8 is a little heavier and is offered in a wider range of chamberings. Parts for

1716-586: The barrel and is designed to withstand pressures significantly exceeding the Mauser 98 –type bolt-action rifles. The Blaser R93 displays a locking surface of 66 mm (0.102 in ) compared to 56 mm (0.087 in ) for the Mauser 98. The bolt is symmetric and self-centering, providing a basis for increased accuracy. The stressed parts are made out of hammer forged steel and plasma nitrided to provide corrosion resistance and mechanical strength. In addition to

1768-432: The barrel did not have a stamped serial number anymore, and claimed the serial number appeared to have been reapplied by hand. He also claimed his rifle originally had a front sight mounted to it which was missing on the returned barrel. In August 2014, Svensk Jakt wrote that another Swede, Tony Kristoffersson, had experienced an explosion with his R93 while on a Beaver hunt the same year. He described that his rifle had made

1820-678: The collet against the chuck cap, tightening around the cutter shank, hence "Autolock". The correct installation sequence as per the original specification is: As the tool is used further rotation tightens the collet and the centering pin ensures that tool extension and alignment remain unchanged. A spanner is only required to release the locked collet. While threaded shank "Autolock" tools may be gripped by plain collets, such as ER, plain shank tools should never be used in an "Autolock" collet as they will not be properly clamped or aligned. R8 collets were developed by Bridgeport Machines, Inc. for use in milling machines. Unusually, R8 collets fit into

1872-559: The collet is what holds the bit in place. In the U.S. it is generally for 0.25 or 0.5 inches (6.4 or 12.7 mm) bits, while in Europe bits are most commonly 6, 8 or 12 mm (0.24, 0.31 or 0.47 in). The collet nut is hexagonal on the outside so it can be tightened or loosened with a standard wrench , and has threads on the inside so it can be screwed onto the motor arbor . Many users (hobbyists, graphic artists, architects, students, and others) may be familiar with collets as

1924-422: The collet provide precise, repeatable radial centering and axial concentricity. The basic mechanism fixes four of the six degrees of kinematic freedom, two locations and two angles. Collets may also be fitted to precisely align parts in the axial direction (a fifth degree of freedom) with an adjustable internal stop or by a shoulder stop machined into the internal form. The remaining sixth degree of freedom, namely

1976-548: The collet's advantage over other types of chuck is that it combines all of the following traits into one chuck; making it highly useful for repetitive work. There are many types of collet used in the metalworking industry. Common industry-standard designs are R8 (internally threaded for mills ) and 5C (usually externally threaded for lathes ). There are also proprietary designs which only fit one manufacturer's equipment. Collets can range in holding capacity from zero to several inches in diameter. The most common type of collet grips

2028-403: The cutter shank must be an exact match. The tightening sequence of Autolock collets is widely misunderstood. The chuck cap itself does not tighten the collet at all, with the cap tight and no tool inserted the collet is loose in the chuck. Only when a cutter is inserted will the collet be pressed against the cap taper. The back of the cutter engages with a centering pin and further turning drives

2080-412: The cylinder head. It may be realized that the retainer does not budge when the valve spring compressor is used, this is due to a buildup of carbon which over time has locked the retainer and collets slightly. A slight sharp tap on the backside of the valve spring compressor above the valve stem should free the retainer allowing the springs to be compressed whilst retrieving the split collet. On reassembly it

2132-461: The damages to the firearm almost certainly came from a combination of an overpressure and a problem with the casing of the cartridge. Svensson told the Swedish hunting and firearms magazine Svensk Jakt that he had difficulties getting his firearm back from the testing, and that it had been modified when he finally received it. He stated that the chamber and bolt head had been chopped off, and that

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2184-431: The face remaining in place. Collets allowing a wider range of workholding by means of springs or elastic spacers between jaws; such collets were developed by Jacobs (Rubberflex), Crawford (Multibore), and Pratt Burnerd, and are in some cases compatible with certain spring collet chucks. The Morse taper is a common machine taper frequently used in drills, lathes and small milling machines. Chucks for drilling usually use

2236-400: The fact that they are bought in a soft (unhardened) state and machined as needed). Yet another type of collet is a step collet which steps up to a larger diameter from the spindle and allows holding of larger workpieces. In use, the part to be held is inserted into the collet and then the collet is pressed (using a threaded nose cap) or drawn (using a threaded drawbar) into the body which has

2288-427: The invention of collets. Watchmakers' lathes all take collets which are sized by their external thread. The most popular size is 8 mm which came in several variations but all 8 mm collets are interchangeable. Lorch, a German Lathe maker, started with 6 mm collets and the first Boleys used a 6.5 mm collet. 6 mm collets will fit into a 6.5 mm lathe but it is a poor practice. Another popular size

2340-494: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=R93&oldid=1121311304 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Blaser R93 In 2002, more than 100,000 complete Blaser R93 rifles had been produced. By 2017, more than 200,000 R93 rifles had been produced, but it

2392-415: The machine taper itself (i.e. there is no separate chuck) and tools with integral R8 taper can also be directly fitted. R8 was developed to allow rapid tool changes and requires an exact match between collet and tool shank diameter. R8 collets have a keyway to prevent rotation when fitting or removing, but it is the compressed taper and not the keyway that provides the driving force. Collets are compressed by

2444-702: The maximum safe gas pressure for the round. In July 2009, Spaniard Jesus Nieto had an accident near Madrid in Spain where his R93 rifle chambered for 7mm Remington Magnum exploded, causing the bolt carrier to hit and damage his maxilar bone . The accident was determined by the shooter to be due to faulty ammunition leaving a fired bullet stuck in the barrel, causing an explosion on the subsequent shot. The shooter stated that he had used Remington Safari Grade commercial ammunition. In July 2014, 69-year-old Christer Svensson experienced an accident where his R93 chambered for .30-06 Springfield exploded while loading his rifle on

2496-432: The part of an X-Acto or equivalent knife that holds the blade. Another common example is the collet that holds the bits of a Dremel or equivalent rotary tool. In semiconductor industry, a die collet is used for picking a die up from a wafer after die cutting process has finished, and bonding it into a package. Some of them are made with rubber, and use vacuum for picking. Most internal combustion engines use

2548-435: The primary lockup by the bolt head into the barrel, the R93 also features a secondary lockup for added safety. While secondary lockup on turn bolt rifles is achieved with the bolt handle, secondary lockup on the R93 this is achieved with a camplate which supports the locked action against a hardened steelplate in the rear part of the magazine-box. The bolt knob uses M6 threads, enabling the use of aftermarket bolt knobs. Below

2600-490: The rotation of the part in the collet, may be fixed by using square, hexagonal, or other non-circular part geometry. The "ER" collet system, developed and patented by Swiss manufacturer Rego-Fix in 1972, and standardized as DIN 6499, is the most widely used tool clamping system in the world and today available from many producers worldwide. The standard series are: ER-8, ER-11, ER-16, ER-20, ER-25, ER-32, ER-40, and ER-50. The "ER" name came from an existing "E" collet (which were

2652-463: The shot. Per US importer armusa.com, http://armusa.com/SigarmsRifles6.htm "Also contributing to the Blaser's performance are its patented sear-free trigger mechanism and completely free-floated barrel." A free-floated barrel is a common modern accurizing technique, but searless triggers are quite novel. The R93 straight-pull bolt action locks by a 14-lug radial collet in a 360 degrees groove in

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2704-474: The trigger being placed under the magazine. The rifle also has a reputation for being easy to disassemble and reassemble which can be an advantage when doing maintenance or during travelling, and has a reputation for having a repeatable zero upon reassembly. The Blaser is unique because the scope mounts on the barrel instead of the receiver. A Scope/barrel assembly can be removed and replaced with no change in zero. In 2009, Blaser and Carl Zeiss AG began offering

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