The 6.5×68mm

rebated rim A rim is an external flange that is machined, cast, molded, stamped, or pressed around the bottom of a firearms cartridge. Thus, rimmed cartridges are sometimes called "flanged" cartridges. Almost all cartridges feature an extractor or headspacing ...

bottlenecked

centerfire Two rounds of .357 Magnum, a centerfire cartridge; notice the circular primer in the center A centerfire cartridge is a firearm metallic cartridge whose primer is located at the center of the base of its casing (i.e. "case head"). Unlike rim ...

rifle A rifle is a long-barreled firearm designed for accurate shooting, with a barrel that has a helical pattern of grooves ( rifling) cut into the bore wall. In keeping with their focus on accuracy, rifles are typically designed to be held with ...

cartridge Cartridge may refer to: Objects * Cartridge (firearms), a type of modern ammunition * ROM cartridge, a removable component in an electronic device * Cartridge (respirator), a type of filter used in respirators Other uses * Cartridge (surname), a ...

(also known as the 6.5×68mm RWS, 6.5×68mm Schüler, or the 6.5×68mm Von Hofe Express) and its sister cartridge the

8×68mm S The 8×68mm S rebated rim bottlenecked centerfire rifle cartridge was developed in the 1930s by August Schüler of the ''August Schüler Waffenfabrik, Suhl, Germany'' as a magnum hunting cartridge that would just fit and function in standard-size ...

were developed in the 1930s by August Schüler from the ''August Schüler Waffenfabrik, Suhl, Germany'' as magnum hunting cartridges that would just fit and function in standard-sized

Mauser 98 The Gewehr 98 (abbreviated G98, Gew 98, or M98) is a German bolt-action rifle made by Mauser, firing cartridges from a five-round internal Clip (ammunition), clip-loaded magazine. It was the German service rifle from 1898 to 1935, when it was r ...

bolt-action 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 ...

rifles. This is one of the early examples where a completely new rifle cartridge (the 6.5×68mm and 8×68mm S have no other cartridge as parent case) was developed by a

gunsmith A gunsmith is a person who repairs, modifies, designs, or builds guns. The occupation differs from an armorer, who usually replaces only worn parts in standard firearms. Gunsmiths do modifications and changes to a firearm that may require a very h ...

to fit a specific popular and widespread type of rifle.

History

The German

ammunition Ammunition (informally ammo) is the material fired, scattered, dropped, or detonated from any weapon or weapon system. Ammunition is both expendable weapons (e.g., bombs, missiles, grenades, land mines) and the component parts of other weap ...

manufacture
RWS
(Rheinisch-Westfälischen Sprengstofffabrik) introduced both cartridges commercially in the spring of 1939. With the official certification of the .375 Hölderlin and the 8.5×68mm Fanzoj this German 68 mm "family" of magnum rifle cartridges that all share the same basic cartridge case got expanded in the 21st century. The cartridges in this German 68 mm cartridge "family" are, in the order of development: * 8×68mm S (1939) * 6.5×68mm (1939) *

.375 Hölderlin The .375 H&H Magnum also known as .375 Holland & Holland Magnum is a Caliber, medium-bore rifle cartridge introduced in 1912 by London based gunmaker Holland & Holland. The .375 H&H cartridge Belted magnum, featured a belt to ensure the correct ...

(9.5×68mm) (2007) * 8.5×68mm Fanzoj (2012) The M 98 bolt actions and magazine boxes of standard military Mauser 98 rifles have to be adapted by a competent

to function properly with these magnum cartridges since the cases are longer and have a larger diameter than the 8×57mm service cartridges. In properly adapted standard military

Gewehr 98 The Gewehr 98 (abbreviated G98, Gew 98, or M98) is a German bolt-action rifle made by Mauser, firing cartridges from a five-round internal clip-loaded magazine. It was the German service rifle from 1898 to 1935, when it was replaced by the Ka ...

Karabiner 98k The Karabiner 98 kurz (; "carbine 98 short"), often abbreviated Karabiner 98k, Kar98k or K98k and also sometimes incorrectly referred to as a K98 (a K98 is a Polish carbine and copy of the Kar98a), is a bolt-action rifle chambered for the 7.92×5 ...

service rifles the large 6.5×68mm cartridges are, however, praised for very smooth and reliable feeding. The widespread availability of standard size Mauser 98 rifles and the fact that the .375 H&H Magnum cartridge and its necked down version the .300 H&H Magnum with approximately 72.4 mm case length were too long to fit in standard sized

rifles makes the shorter 6.5×68mm, 8×68mm S and .375 Hölderlin interesting chambering options.

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

spoiled the commercial introduction and spread of the 6.5×68mm. The cartridge became popular after World War II due to its high performance and flat

trajectory A trajectory or flight path is the path that an object with mass in motion follows through space as a function of time. In classical mechanics, a trajectory is defined by Hamiltonian mechanics via canonical coordinates; hence, a complete traj ...

, when German hunters were allowed again to own and hunt with full bore rifles. The 6.5×68mm's performance also made it that hunters who had problems with handling magnum cartridge recoil stepped down to less powerful but adequate medium cartridges like the

6.5×57mm Mauser The 6.5×57mm Mauser (designated as the 6,5 × 57 by the C.I.P.) is a smokeless powder rimless bottlenecked centerfire rifle cartridge developed by Paul Mauser and introduced in 1893–94. Overview The 6.5×57mm Mauser was designed and intro ...

, 7.92×57mm Mauser,

7×64mm The 7×64mm (also unofficially known as the 7×64mm Brenneke, though its designer's name was never officially added as a part of the cartridge name) is a rimless bottlenecked centerfire cartridge developed for hunting. As is customary in Europe ...

(Brenneke) or

.30-06 Springfield The .30-06 Springfield cartridge (pronounced "thirty- aught-six" ), 7.62×63mm in metric notation, and called the .30 Gov't '06 by Winchester, was introduced to the United States Army in 1906 and later standardized; it remained in military use ...

(also known as the 7.62×63mm in metric countries). Recoil sensitive shooters can fit an efficient

muzzle brake A muzzle brake or recoil compensator is a device connected to, or a feature integral to the construction of, the muzzle or barrel of a firearm or cannon that is intended to redirect a portion of propellant gases to counter recoil and unwanted ...

to significantly reduce the amount of recoil. With the help of a muzzle brake, the 6.5×68mm's recoil is reduced to tolerable levels.

Cartridge dimensions

Extremely thick brass results in 'only' 5.58 ml (86

grains A grain is a small, hard, dry fruit (caryopsis) – with or without an attached hull layer – harvested for human or animal consumption. A grain crop is a grain-producing plant. The two main types of commercial grain crops are cereals and legume ...

) H₂O cartridge case capacity for the 6.5×68mm. A rare feature of this German rimless bottlenecked

cartridge design is that it has a slightly rebated rim (P1-R1 = 0.3 mm). A sign of the era in which the 6.5×68mm was developed are the gently sloped shoulders. The exterior shape of the case was designed to promote reliable case feeding and extraction in

rifles, under extreme conditions. 6.5×68mm maximum C.I.P. cartridge dimensions. All sizes in millimetres (mm). Americans would define the shoulder angle at alpha/2 ≈ 14.53 degrees. The common

rifling In firearms, rifling is machining helical grooves into the internal (bore) surface of a gun's barrel for the purpose of exerting torque and thus imparting a spin to a projectile around its longitudinal axis during shooting to stabilize the pro ...

twist rate In firearms, rifling is machining helical grooves into the internal (bore) surface of a gun's barrel for the purpose of exerting torque and thus imparting a spin to a projectile around its longitudinal axis during shooting to stabilize the pro ...

for this cartridge is 250 mm (1 in 9.84 in), 4 grooves, Ø lands = 6.45 mm, Ø grooves = 6.70 mm, land width = 3.50 mm and the primer type is large rifle magnum. According to the official C.I.P. (

Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives Commission or commissioning may refer to: Business and contracting * Commission (remuneration), a form of payment to an agent for services rendered ** Commission (art), the purchase or the creation of a piece of art most often on behalf of anothe ...

) guidelines the 6.5×68mm case can handle up to 440 MPa (63817 psi) piezo pressure. In C.I.P. regulated countries every rifle cartridge combo has to be proofed at 125% of this maximum C.I.P. pressure to certify for sale to consumers. When the 6.5×68mm was introduced in 1939 it probably held the title of fastest production cartridge on the market. Nowadays there are commercial cartridges on the market which offer even higher muzzle velocities. The American

.264 Winchester Magnum The .264 Winchester Magnum is a belted, bottlenecked rifle cartridge. Except for the .244 H&H Magnum and .257 Weatherby Magnum, it is the smallest caliber factory cartridge derived from the Holland & Holland belted magnum case. It was introdu ...

cartridge introduced in 1959 and the French 6.5×63mm Messner Magnum are probably the closest ballistic twins of the 6.5×68mm.

The 6.5×68mm in field use

German and Austrian hunters use the powerful, high velocity 6.5×68mm for long-range hunting in mountainous terrain like the

Alps The Alps () ; german: Alpen ; it, Alpi ; rm, Alps ; sl, Alpe . are the highest and most extensive mountain range system that lies entirely in Europe, stretching approximately across seven Alpine countries (from west to east): France, Sw ...

mountain range A mountain range or hill range is a series of mountains or hills arranged in a line and connected by high ground. A mountain system or mountain belt is a group of mountain ranges with similarity in form, structure, and alignment that have arise ...

. The 6.5×68mm as a pure civil cartridge can be used in countries which ban civil use of former or current military ammunition. Since there are not many factory loads available
RWS
offers only 2 factory loads) and due to its good field reputation, the 6.5×68mm is often used by reloaders. They have used this cartridge extensively to create powerful loads by

handloading Handloading, or reloading, is the practice of making firearm cartridges by assembling the individual components (case, primer, propellant, and projectile), rather than purchasing mass-assembled, factory-loaded ammunition. The term ''hand ...

. Factory rifles in 6.5×68mm normally have 250 mm to 280 mm (1 in 9.8 to 11 inch)

s, which are too slow to adequately stabilize modern long heavy 6.5 mm bullets. This slow twist rate was chosen since the bullet jackets used in the 1930s were not strong enough to cope with the forces generated by the magnum muzzle velocities of the 6.5×68mm. The traditional 6.5×68mm twists nowadays inhibits its potential. To make the 6.5×68mm an awesome long-range cartridge,

rifle barrel A gun barrel is a crucial part of gun-type weapons such as small firearms, artillery pieces, and air guns. It is the straight shooting tube, usually made of rigid high-strength metal, through which a contained rapid expansion of high-pressure ga ...

s with a 200 mm to 230 mm (1 in 7.9 to 9 inch)

are a better choice. Due to the large case capacity in relation to the 6.5 mm (.264 inch) caliber bore size the 6.5×68mm is very harsh on barrels. The 6.5×68mm typically wears out a rifle barrel in 500 to 1000 rounds. A lot of thorough barrel cleaning (after every 5 shots) and carefully avoiding long strings of shots help to minimize barrel wear. This makes this cartridge impractical for most competition shooters who tend to fire a lot of rounds in practice to acquire and maintain expert long-range marksmanship. Reloaders use the 6.5×68mm as a Jack of all trades long-range cartridge on all European game from

fox Foxes are small to medium-sized, omnivorous mammals belonging to several genera of the family Canidae. They have a flattened skull, upright, triangular ears, a pointed, slightly upturned snout, and a long bushy tail (or ''brush''). Twelve sp ...

roe deer The roe deer (''Capreolus capreolus''), also known as the roe, western roe deer, or European roe, is a species of deer. The male of the species is sometimes referred to as a roebuck. The roe is a small deer, reddish and grey-brown, and well-adapt ...

and

chamois The chamois (''Rupicapra rupicapra'') or Alpine chamois is a species of goat-antelope native to mountains in Europe, from west to east, including the Alps, the Dinarides, the Tatra and the Carpathian Mountains, the Balkan Mountains, the Ril ...

upwards to the big European game like

red deer The red deer (''Cervus elaphus'') is one of the largest deer species. A male red deer is called a stag or hart, and a female is called a hind. The red deer inhabits most of Europe, the Caucasus Mountains region, Anatolia, Iran, and parts of wes ...

and

moose The moose (in North America) or elk (in Eurasia) (''Alces alces'') is a member of the New World deer subfamily and is the only species in the genus ''Alces''. It is the largest and heaviest extant species in the deer family. Most adult mal ...

. These people realized that bullets with different characteristics can be utilized to produce varying effects on game. As with all 6.5 mm cartridges, the big game hunting bullets used in the 6.5×68mm have comparatively high sectional densities for good penetration on suitable size game animals.

The 6.5×68mm as parent case

Cartridges that are not officially registered with nor sanctioned by C.I.P. (Commission Internationale Permanente Pour L'Epreuve Des Armes A Feu Portative) or its American equivalent,

SAAMI The Sporting Arms and Ammunition Manufacturers' Institute (SAAMI, pronounced "Sammy") is an association of American manufacturers of firearms, ammunition, and components. SAAMI is an accredited standards developer that publishes several Americ ...

(Sporting Arms and Ammunition Manufacturers’ Institute) are generally known as

wildcats The wildcat is a species complex comprising two small wild cat species: the European wildcat (''Felis silvestris'') and the African wildcat (''F. lybica''). The European wildcat inhabits forests in Europe, Anatolia and the Caucasus, while the ...

. By blowing out standard factory cases the wildcatter generally hopes to gain extra muzzle velocity by increasing the case capacity of the factory parent cartridge case by a few percent. Practically there can be some muzzle velocity gained by this method, but the measured results between parent cartridges and their 'improved' wildcat offspring is often marginal. Besides changing the shape and internal volume of the parent cartridge case, wildcatters also can change the original caliber. A reason to change the original caliber can be to comply with a minimal permitted caliber or bullet weight for the legal hunting of certain species of game. Wildcats are not governed by C.I.P. or SAAMI rules so wildcatters can capitalize the achievable high operating pressures. It is often reported that modern 68 mm RWS brass can tolerate up to 500 MPa (72519 psi) piezo pressure. Because the 6.5×68mm offers an exceptional sturdy, pressure resistant cartridge case that can relatively easily be reloaded with primers, powder and bullets and hence be reused several times it has become quite popular amongst wildcatters. With the German 68 mm magnum cartridge case as parent case wildcatters have created .25×68, .270×68, 7×68mm, .30×68, .338×68, .375×68 or .416×68 variants.

References

*
6.5x68 reloading data
from Reloader's Nest" The site isn't working any more" * C.I.P. CD-ROM edition 2003 * C.I.P. decisions, texts and tables
free current C.I.P. CD-ROM version download (ZIP and RAR format)

External links

C.I.P. TDCC sheet 6,5 x 68
{{DEFAULTSORT:6.5x68mm Pistol and rifle cartridges Magnum rifle cartridges