.260 Remington: Difference between revisions

{{shortShort description|CartridgeAmerican rifle cartridge}}

{{Use mdy dates|date=FebruaryJuly 20122022}}

| case typecase_type = Rimless, bottleneck

| rifling = 9"1 (229in {{convert|9|in|mm)|0|abbr=on}}

The '''.260 Remington''' (also known as '''6.5-08 A-Square''') cartridge was introduced by Remington in 1997. Many [[wildcat cartridge]]s based on the [[.308 Winchester]] case had existed for years before Remington standardized this round. Although loaded to higher pressures, the ballistics of this cartridge are basically similar to the [[6.5×55mm]] when bullet weights do not exceed 140 grains. When loaded with heavier bullets, the 6.5×55mm is capable of greater velocity.<ref name="lyman">{{Cite book |url=http://marvinstuart.com/firearm/Manuals/Reloading/Reloading%20Manuals/Lyman%20Reloading%20Handbook%20-%2048th%20Edition%20-%202002%20-%20ocr.pdf |title=Lyman's Reloading Handbook |publisher=Lyman Products |year=2002 |editor-last=Griffin |editor-first=Thomas J. |edition=48th |location=Middletown, CT |access-date=2018-06-23}}</ref> Due to its shorter overall length the .260 Remington can be chambered in a shorter length action than the 6.5×55mm.

Because 6.5&nbsp;mm (.264") bullets have relatively high [[ballistic coefficient]]s, the .260 Remington has seen success in rifle competition including bench rest, [[metallic silhouette]], and long range. It is capable of duplicating the trajectory of the [[.300 Winchester Magnum]], while generating significantly lower recoil.<ref name="Zak">{{Cite web |title=The Case for .260 Remington: A Better Cartridge For Practical Long-Range Shooting |url=http://demigodllc.com/articles/the-case-for-260-remington/?p=1 |lastlast1=Smith |firstfirst1=Zak |date=October 1, 2007 |publisher=Demigod LLC |page=[http://demigodllc.com/articles/the-case-for-260-remington/?p=2 2]}}</ref> Also, converting a rifle chambered for the [[.308 Winchester]] (or any of its offspring, such as the [[.243 Winchester]], [[7mm-08 Remington]], [[.358 Winchester]] or [[.338 Federal]]) to .260 Remington generally requires little more than a simple barrel change.

Remington has had a track record of adopting successful wildcat cartridges into the Remington fold by offering rifles and ammunition and at times attaching their name to the cartridge.<ref>{{Cite web |title=Wildcat Cartridges That Went Legit |url=http://www.americanrifleman.org/articles/wildcat-cartridges-went-legit |lastlast1=Simpson |firstfirst1=Layne |date=March 10, 2014 |website=American Rifleman |url-status=dead |archive-url=https://web.archive.org/web/20140710132843/http://www.americanrifleman.org/articles/wildcat-cartridges-went-legit |archive-date=July 10, 2014 |access-date=June 15, 2014}}</ref> Like many cartridges such as the .22–250 Remington, .25-06 Remington, and 7&nbsp;mm-08 Remington, the .260 Remington started its life as a wildcat cartridge called the 6.5-08, and was eventually released as a commercial cartridge by Remington. However, Remington was not the first to attempt to standardize the cartridge. LTC Arthur Alphin and his company A-Square LLC submitted the first proposal and drawings to SAAMI for the standardization of the cartridge. Remington filed similar papers with SAAMI to do the same a few months later. When the dust settled, the 6.5-08 would be called the .260 Remington instead of 6.5–08 A-Square.

The 6.5-08 cartridge was created simply by necking down the .308 Winchester.<ref name="SundraP142">{{Cite magazine |lastlast1=Sundra |firstfirst1=Jon R. |year=2009 |orig-year=Nov-Dec |title=Guns & Ammunition |magazine=Safari |publisher=Safari Club International |page=142}}</ref> [[Handloading|Handloaders]] and [[Wildcat cartridge|wildcatters]] can easily form .260 cases by necking down the [[7mm-08 Remington]] or necking up the [[.243 Winchester]] (both based on the same .308 case).<ref name=SundraP142/> Since the parent cartridges were readily available for low cost, the 6.5-08 was often an economical alternative to cartridges such as the 6.5×55mm. What the 6.5-08 provided over the .243 Winchester, .308 Winchester, and to a lesser degree the 7mm-08 Remington was bullets with excellent ballistic coefficients and sectional densities.

:[[Image:260Remington.png|450px|alt=260 Remington Schematic|alt=.260 Remington schematic diagram conforming to SAAMI dimensions|.260 Remington schematic complying with SAAMI specifications]]

SAAMI recommends a barrel with a 6 groove contour and a twist rate of one revolution every {{cvt|9|in|mm|0}} with each groove having a width of {{cvt|.095|in|mm|2}}. The recommended bore diameter is {{cvt|.256|in|mm|2}} and the groove diameter is {{cvt|.264|in|mm|2}}. SAAMI recommends that rifling commence at {{cvt|.221|in|mm|2}} from the chamber mouth. SAAMI also recommends a pressure of {{cvt|60000|psi|MPa|2}}<ref>{{Cite web |title=SAAMI datasheet — 260 Remington |url=http://www.saami.org/PubResources/CC_Drawings/Rifle/260%20Remington.pdf |publisher=[[Sporting Arms and Ammunition Manufacturers' Institute|SAAMI]] |url-status=dead |archive-url=https://web.archive.org/web/20160328081317/https://saami.org/PubResources/CC_Drawings/Rifle/260%20Remington.pdf |archive-date=2016-03-March 28, 2016}}</ref>

The .260 Remington being a .264 caliber (6.5&nbsp;mm) has certain advantages: the bullets have good sectional density (penetrating ability) and a good selection of bullet weights. Factory ammunition usually are loaded with bullets weighing anywhere from {{convert|120|gr|g|abbr=on}} to {{convert|140|gr|g|abbr=on}}. Bullets available to the reloader range from {{convert|85|gr|g|abbr=on}} to {{convert|160|gr|g|abbr=on}}. The {{convert|120|gr|g|abbr=on}} bullet has a sectional density of 0.246 which is similar to a {{convert|165|gr|g|abbr=on}} .308 caliber (7.62&nbsp;mm) bullet. The {{convert|140|gr|g|abbr=on}} bullet has a sectional density of 0.287 which is similar to that of a {{convert|190|gr|g|abbr=on}} .308 caliber (7.62&nbsp;mm) bullet. The {{convert|160|gr|g|abbr=on}} bullet which has a sectional density of 0.328 is similar in sectional density to a {{convert|220|gr|g|abbr=on}} .308 caliber (7.62&nbsp;mm) bullet. As sectional density plays a large factor in penetration, the .264 caliber (6.5&nbsp;mm), though a diminutive caliber from a North American point of view, has had excellent results in the field. Walter D.M. Bell, who was known to have shot over a thousand elephants in his lifetime, used, among others, .264 caliber ([[6.5×54mm Mannlicher–Schönauer|6.5 mm]]) and .284 caliber ([[7×57mm Mauser|7 mm]]) rifles to do so.<ref name="chuckhawks.com">{{Cite web |title=W.D.M. Bell and His Elephants |url=http://www.chuckhawks.com/bell_elephants.htm |lastlast1=Passmore |firstfirst1=James |year=2008 |publisher=chuckhawks.com |access-date=June 26, 2012}}</ref><ref name="huntersguide">{{Cite book |lastlast1=Van Zwoll |firstfirst1=Wayne |url=https://books.google.com/books?id=rl6XtAEACAAJ |title=The Hunter's Guide to Accurate Shooting: How to Hit What You're Aiming at in Any Situation |publisher=The Lyons Press |year=2004 |isbn=978-1-59228-490-0 |pages=64 |quote=Known in some circles as the .275 Rigby, it was a cartridge Bell was to make famous.}}</ref>

The .260 Remington, while having a slightly lesser case capacity than the 6.5×55mm, is loaded to higher pressure levels. The opposite is true when comparing the .260 Remington to the 6.5mm Creedmoor: They are nearly-identical but the Creedmoor can take a higher [[chamber pressure]] than the .260 Remington, leading the Creedmoor to have more room for a longer bullet (more aerodynamically efficient, higher [[sectional density]] than most shorter bullets) in a given magazine length or [[cartridge overall length]] than the .260 Remington's maximum projectile length or [[ogive]] length, and yet the .260 Remington only has a similar muzzle velocities as the 6.5 Creedmoor for a given projectile weight,<ref>{{Cite web |title=Take Aim at Rifle Reloading Data |url=http://www.hodgdonreloading.com/data/rifle |publisher=Hodgdon Powder Co. |access-date=March 7, 2017 |archive-date=March 1, 2014 |archive-url=https://web.archive.org/web/20140301164524/http://www.hodgdonreloading.com/data/rifle |url-status=dead }}</ref> despite the .260 Remington's larger case capacity and longer brass casing. However, for the same reasons (higher chamber pressure than the 6.5x55 Swede and shorter brass casing), the .260 Remington outperforms the 6.5x55 Swede. Typically, the .260 Remington is loaded with a {{convert|120|gr|g|abbr=on}} bullet at {{convert|2890|ft/s|m/s|abbr=on}} and the {{convert|140|gr|g|abbr=on}} bullet at {{convert|2750|ft/s|m/s|abbr=on}}. In contrast, Norma of Sweden loads the 6.5×55mm with a {{convert|120|gr|g|abbr=on}} bullet at {{convert|2822|ft/s|m/s|abbr=on}} and the {{convert|140|gr|g|abbr=on}} bullet at {{convert|2690|ft/s|m/s|abbr=on}}.

Due in large part to its parentage, the .260 Remington has been adopted into tactical and target shooting rifles. Any rifle which is chambered for 7.62×51mm NATO or .308 Winchester can be converted with only the addition of an appropriate barrel to the .260 Remington. Companies such as Lewis Machine & Tool (LMT), [[ArmaLite]], LaRue, and DPMS Panther Arms, McMillan Firearms (makers of the Tubb 2000), and KMW are among several companies which currently manufacture tactical rifles for use with this cartridge.<ref name=Zak/> The 6.5&nbsp;mm (.264 caliber) bullets have favorable ballistic coefficients and have been adopted for target shooting, especially in the Scandinavian nations. Tubbs manufactures rifles for competition one of which went on to win the NRA HP Championship in 2010.<ref name="AccurateShooter" />

The .260 Remington has become popular with [[metallic silhouette]] shooters. The 2014 NRA National Championship equipment survey lists the .260 Remington as most popular caliber for both the high power rifle and high power hunterhunting rifle competition.<ref>{{Cite conference |title=Final Results Bulletin |url=http://compete.nra.org/documents/pdf/compete/silh-natpdf/14-HPR-HPHR-Final-Bulletin.pdf |conference=2014 NRA High Power Rifle&thinsp; /&thinsp; High Power Hunting Rifle National Silhoutte Championships, July 18–20, 2014, Raton, New Mexico |publisher=[[National Rifle Association|NRA of America]] |archive-url=https://web.archive.org/web/20151010034221/http://compete.nra.org/documents/pdf/compete/silh-natpdf/14-HPR-HPHR-Final-Bulletin.pdf |archive-date=October 10, 2015 |access-date=24 March 24, 2017 |url-status=dead}}</ref>

The cartridge that is now popularly known as the .260 Remington was submitted for standardization under [[SAAMI]] by the A-Square Company in 1996, several months prior to Remington announcing their plans to introduce the cartridge under their own name. A-Square's submission was called the 6.5-08 A-Square. Some users continue to refer to the cartridge under this name.<ref>{{Cite book |lastlast1=Barnes |firstfirst1=Frank C. |url=https://books.google.com/books?id=qt5rewAACAAJ |title=Cartridges of the World |last2=McPherson |first2=M. L. |publisher=Dbi Books |year=2000 |isbn=978-0-87341-909-3 |edition=9th}}</ref>

Since the acceptance of the submission by Remington Arms for the standardization of the 6.5-08 cartridge by SAAMI, A-Square has dropped the cartridge from their line of cartridges chambered for their rifles and no longer offers ammunition in this cartridge. Instead A-Square LLC has gone on to produce rifles and ammunition for the [[6.5-06 A-Square]] cartridge which is based on the [[.30-06]] Springfield]] necked down to .264 caliber (6.5 mm). This cartridge provides over a {{convert|200|ft/s|m/s|abbr=on}} velocity advantage over the .260 Remington.

* [[List6mm of rifle cartridgescaliber]]

* [[6.55mm Creedmoor]]

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