| What I am calling the "Super .338 Magnums" are a series of .338 calibre cartridges intended to take advantage of the generally excellent sectional density (SD) and ballistic coefficient (BC) of .338" bullets to create the ultimate long range cartridge. All of these cartridges are based on outsized cases (usually something along the lines of a blown-out, necked-down .416 Rigby) and were designed to drive a 250 grain bullet at a muzzle velocity (MV) of 3000 fps or more. They are larger and have more powder capacity than the .338 Remington Ultra Mag and .340 Weatherby Magnum.The purpose of most of these cartridges is the taking of large, heavy game at long range. The exception is the .338 Lapua Magnum, which was originally designed as an ultra-long range sniper cartridge for military use. And even the .338 Lapua has made the transition to long range big game cartridge..338 Lapua MagnumThe .338 Lapua Magnum dates back to 1983 when it originated as a U.S. military project. The design goal was a 250 grain bullet at 3000
fps.
Early experiments conducted by Research Armament Company in the U.S. used a necked down .416 Rigby case, but the ultimate version of the 8.58x71mm (.338 Lapua) is based on a new and unique case.In 1987 Lapua of Finland commercialised the cartridge that now bears its name and secured CIP approval. (CIP is the European equivalent of SAAMI in the U.S.) Lapua and Norma of Sweden produce factory loaded ammunition in .338 Lapua. Rifles are offered by Dakota and Sako.The .338 Lapua Magnum uses a large but conventional rimless bottleneck case. It has a rim diameter of .588", and an overall cartridge length of 3.681". It is an impressive looking cartridge.Available reloading data indicates that a 250 grain bullet can be driven at a MV of 3000 fps with ME of 4995 ft. lbs. from the .338 Lapua. Lapua factory loads drive a 250 grain Lock Base soft point bullet at a MV of 2974 fps or a 275 grain A-Frame bullet at a MV of 2581 fps. The 8.58x71mm military load uses a 250 grain spitzer-boat tail FMJ bullet at a MV of 2950 fps with muzzle energy (ME) of 4830 ft. lbs. This round is considered effective for sniping at 1500 meters!.338-378 Weatherby MagnumAs the name implies, Weatherby's ultimate .338 is based on a necked-down .378 Weatherby Magnum case. Both Elmer Keith and Roy Weatherby experimented with necking-down the big .378 case to accept .338" bullets, but these experiments remained wildcats for almost 30 years. Around 1999, long after the death of both men, the Weatherby company finally introduced the .338-378 Weatherby Magnum as a commercial cartridge.This huge belted case incorporates the signature double radius Weatherby shoulder. It has a .579" rim diameter and a maximum case length of 2.913". The overall cartridge length is 3.763".All Weatherby rifles in .338-378 come standard with 28" barrels and include the company's Accubrake muzzle brake. This device is necessary to moderate the heavy recoil of the cartridge. Models available in .338-378 include the TRM, Accumark, and Synthetic.Factory loaded ammunition is available from Weatherby with 200 grain, 225 grain, and 250 grain spitzer bullets. The 250 grain bullet is the popular Nosler Partition. The MV of this load is 3060 fps and the ME is 5197 ft. lbs. The 400 yard figures are 2297 fps and 2927 ft. lbs. Weather ballistics are as follows: +3.5" at 100 yards, +4.2" at 200 yards, 0 at 300 yards, -9.8" at 400 yards, and -26.4" at 500 yards.Handloaders can come pretty close to these velocities. The fifth edition of the Hornady Handbook of Cartridge Reloading shows maximum loads with a MV of 3000 fps. The maximum loads in the fifth edition of the Nosler Reloading Guide are quite similar. The Optimum Game Weight Formula shows that a 250 grain .338 bullet at a MV of 3000 fps has an optimum game weight of 1100 pounds at 400 yards.These ballistics make it obvious that the long range killing power of the .338-378, like all of these .338 super magnums, exceeds the skill of all but the tiniest minority of shooters. Never-the-less, the .338-378 Weatherby Magnum is probably the best known of the .338 super magnums, and Weatherby rifles and ammunition are widely distributed, something that cannot be said for the others.8.59mm TitanLazzeroni designed the 8.59mm (.338) Titan in 1994. It is based on a very large case that is proprietary to Lazzeroni. This case is rimless bottleneck type with a 30 degree shoulder angle. The rim diameter is .577", the case length is 2.8", and the overall cartridge length is 3.75".The peculiar metric designations of Lazzeroni rifles and cartridges are based on their groove diameter, rather than the bore diameter measurement typically used by Europeans. Thus a 7mm becomes a 7.21mm, a .300 becomes a 7.82mm, and a .338 becomes an 8.59mm. Regardless of nomenclature, the Titan uses the same .338" bullets as the other super magnums described in this article.Lazzeroni factory loaded ammunition is available with 185 grain, 200 grain, 225 grain, and 250 grain bullets. The 250 grain bullet is the Swift A-Frame. The approximate MV of this load is 3100 fps and the ME is 5336 ft. lbs. The 400 yard figures are 2379 fps and 3143 ft. lbs. The following trajectory applies: +3.3" at 100 yards, +4" at 200 yards, 0 at 300 yards, and -9.3" at 400 yards. These figures were calculated for the standard conditions used for other factory loaded cartridges.Lazzeroni claims a somewhat higher velocity and flatter trajectory, but if one reads the fine print on the Lazzeroni ballistics table one discovers that it was calculated for a higher altitude (3000') than standard ballistics tables (1000') in order to take advantage of the thinner air, which offers less drag. Also, Lazzeroni assumes a line of sight 2" above the line of bore, rather than the traditional 1.5", to further flatten the apparent trajectory of their cartridges.The Titan was designed specifically for shooting heavy game at long range. To capitalize on the performance potential of this cartridge, Lazzeroni rifles in the caliber come with 27" barrels. Lazzeroni rifles and ammunition are neither inexpensive nor thick on the ground..338 Excaliber & .338 A-SquareThe .338 Excaliber was introduced in 1994 by A-Square. It is A-Square's latest foray into the field of long range medium bore cartridges. An earlier attempt, the .338 A-Square, was designed by Arthur Alphin in 1974.The .338 A-Square is based on a necked-down .378 Weatherby belted magnum case with a conventional (not double radius) shoulder angle of 35 degrees and a cartridge overall length (COL) of 3.67". The .338 Excaliber is based on a standard (not belted) rimless bottleneck case with the same rim diameter as the .378 Weatherby, but slightly greater powder capacity than the .338 A-Square or .338-378 Weatherby. The COL of the .338 Excaliber is 3.75".The performance of the two cartridges is actually pretty similar. Rifles and factory loaded ammunition for both cartridges are provided by A-Square. Reloading data can be found in the interesting A-Square Handloading Manual Any Shot You Want..338 A-Square factory loads come with a 200 grain spitzer bullet, a 250 grain spitzer-BT bullet, and three 250 grain (Triad) round nose bullets. A-Square claims a MV of 3120 fps and ME of 5403 ft. lbs. for their Triad of 250 grain round nose bullets. These three bullets are designed for specific types of heavy or dangerous game at medium ranges. The BC and SD of these bullets are identical. The trajectory figures look like this: +1.5" at 100 yards, 0 at 200 yards, -7.1" at 300 yards, and -20.4" at 400 yards.A-Square factory loads for the .338 Excaliber are offered with the same selection of 200 grain and 250 grain bullets as the .338 A-Square. In the case of the Excaliber, both the 250 grain spitzer-BT and the Triad of 250 grain RN bullets are loaded to the very high MV of 3250 fps and ME of 5863 ft. lbs. Naturally, the spitzer-BT bullet benefits more from this increased velocity. The trajectory of that load looks like this: +2.7" at 100 yards, +3.4" at 200 yards, 0 at 300 yards, and -7.8" at 400 yards.The performance of the A-Square factory loads for either of their .338 super magnums can be duplicated by reloaders. The .338 Excaliber has the greatest case capacity and consequently the highest potential performance of the .338 super magnums.ConclusionReloading data indicates that a 250 grain bullet can be driven at a MV of 3000 fps with ME of 4995 ft. lbs. from any of the super .338 magnum cartridges. A quick look at the "Rifle Trajectory Table" shows that such a load using a 250 grain spitzer bullet (BC .473) would have a maximum point blank range (+/- 3") of 297 yards. This can be taken as typical performance.The biggest disadvantage to any of these .338 super magnums is their fierce recoil and muzzle blast, which is way beyond the level that most shooters can tolerate. For instance, according to the "Rifle Recoil Table" a shooter with a 9.5 pound rifle in .338-378 Weatherby, shooting a 250 grain bullet at a MV of 3000 fps, is facing 46.5 ft. lbs. of recoil energy. It is strongly recommended that any of the super .338 Magnum rifles be equipped with an efficient muzzle brake, and that the rifle be fired only when the shooter is wearing maximum hearing protection.There is no doubt that the .338 super magnums can deliver terrific power at long range. My article "The .338 Lapua Magnum" relates that the .338 Lapua, for example, has a maximum optimal range of 442 yards for 1000 pound game animals. However, as the same article concludes, "Whether anyone is ever justified in shooting at heavy game at such ranges is another question." |
HISTORY AND DEVELOPMENT OF THE .338 LAPUA MAGNUMOriginally developed as a military cartridge, the .338 LAPUA Magnum may well be seen by small-arms historians as one of the most important cartridges developed in the latter part of the 20th century. The .338 fills an important but previously unfilled tactical niche between 7.62mm and .50 caliber sniper rifles, since it is capable of delivering reliable hits to 1,500 meters. Thanks to innovative bullet designs developed at Lapua, the .338 LAPUA Magnum also makes a compelling cartridge for long-range target shooting and hunting big game such as moose, bison and bear. The .338 LAPUA Magnum is an important cartridge to military snipers because it significantly outperforms the 7.62x51 mm (.308 Winchester) round, which is the most common cartridge used in the sniper rifles of NATO and other Western countries. Rifles chambered in 7.62x51 mm tend to be reasonably light and maneuverable while providing a good mix of accuracy and penetration out to about 600 meters with conventional ammo and to about 900 meters with VLD (Very Low Drag) ammo. The .300 Winchester Magnum, which is increasingly being fielded in sniper rifles, provides good performance out to about 1,000 meters. That's a long shot, but serious problems in the real world can need solving at greater ranges. In the military environment--whether conducting conventional operations, so-called peace-keeping missions, or special operations--it's not uncommon to come under heavy weapons fire originating a kilometer or more away. There has been considerable interest in fielding precision rifles chambered for the massive .50 BMG (12.7x99rnm) machine gun round to counter such long-range threats, since this round has a maximum effective range of about 2,000 meters. There are several liabilities to .50 BMG precision rifles: (1) they are much bigger and heavier than conventional rifles: (2) their massive recoil impulse makes them unpleasant to shoot: (3) their massive muzzle blast is very unpleasant for both the shooter and his spotter, and therefore tends to cause all but the very best shooters to flinch; (4) muzzle blast tends to kick up debris (not to mention the considerable muzzle flash) that can reveal the shooter's position to hostile forces; and (5) .50 BMG rifles are frequently less accurate than rifles designed for the .338 LAPUA Magnum. Size and weight are important issues since .50 BMG rifles frequently weigh 26 pounds (12 kg) or more without optics. It is safe to say that lighter rifles in this caliber are unpleasant to shoot. Furthermore, rifles built at the lighter end of the .50 BMG envelope have caused more than one separated shoulder or detached retina. Finally, .50 BMG rifles are neither handy nor maneuverable. One can make the argument that .50 caliber rifles should really be viewed as crew-served weapons. While these rifles excel at a long-range anti-materiel role, they don't have the optimum mix of characteristics for long range anti-personnel applications. The .338 LAPUA Magnum is capable of placing reliable hits well beyond a kilometer (0.6 mile), yet the typical .338 rifle only weighs about 2 pounds (I kg) more than a comparable .308 rifle. The weapon is much more pleasant to shoot than a .50 BMG rifle, its muzzle blast and flash are considerable less, and both the rifles and the ammunition provide a more cost-effective option for long-range military sniping. I am aware of no other cartridge that effectively competes with the .338 LAPUA Magnum in bridging the gap between the .308 Winchester and .50 BMG cartridges. In terms of external ballistics, the.338 LAPUA Magnum's 250 grain (16.2 gram) FMJ projectile has a better ballistic coefficient than .30 caliber projectiles, and it is less sensitive to crosswind. Therefore, it should not be surprising that the .338 LAPUA Magnum outperforms the .300 Winchester Magnum, especially at ranges beyond 1,000 meters. I suspect that we'll be seeing a lot more of the .338 LAPUA Magnum cartridge, since a widening circle of end-users are evaluating its merit as a sniping round. The British Ministry of Defence, for example, recently adopted the Accuracy International Model AW Super Magnum chambered in .338 LAPUA Magnum to meet its requirement for a long-range sniper rifle. The Netherlands has adopted .338 rifles as their standard sniping weapon, and several European countries are evaluating .338 rifles as well. Barrett Firearms in the United States is working on three interesting weapons chambered for this round: a bolt-action rifle, a semiautomatic rifle, and a belt-fed machine gun. Other companies producing rifles in .338 LAPUA Magnum include McMillan Brothers in the United States, Sako Ltd. in Finland, and the German companies Mauser Werke Oberndorf GmbH, Heym Jagdwaffen GmbH & Co. KG, Keppeler & Fritz GmbH, and Erma Werke GmbH. Lloyd DeSantis in the United States is even making a scaled-up clone of the AR-15 rifle designed expressly for the.338 LAPUA Magnum. I used Erma's SR 100 Praezisionsgewehr (Precision Rifle) to evaluate the performance of the .338 LAPUA Magnum, which provided almost unbelievable performance at long range.
The Sako TRG-42 cal. .338 LAPUA Magnum rifle from SAKO Ltd., Finland, features an overall length of 1200 mm, a cold forged barrel length of 690 mm, a weight of 5.6 kg without optics, and a five-round detachable box. History of the .338 LAPUA MagnumThe .338 LAPUA Magnum, also known as the 8.6x70mm, was originally developed in 1983 as a long-range sniper cartridge for the U.S. Navy designed to push a 250 grain (16.2 gram) bullet at about 3,000 fps (914 mps). After a series of experiments, the Research Armament Company in the United States designed a round based on a slightly shortened and necked-down .416 Rigby case, building rifles for the Navy that used Hornady bullets and cases from Brass Extrusion Labs. The cartridge went from wildcat to production status when Lapua Ltd. in Finland refined the design at the Navy's request. The standard .416 case was not robust enough to support the average pressures generated by this cartridge, so Lapua kept the outside dimensions the same but beefed up the web area of the case. I should note that average pressures for this cartridge run a bit less than 60,915 psi or 420 MPa, and no single round will exceed 70,052 psi or 483 MPa. Muzzle velocity of production ammunition is a wee bit slower than the original concept, running about 2,950 fps (900 mps) out of the average rifle. This round will still be supersonic at 1.300 yards (1,200 meters), however, while 7.62x51 mm M80ball commonly goes subsonic around 770 yards (704 m). Accuracy and velocity at long range are greatly facilitated by the design of the Lapua projectiles, which have had a reputation for extraordinary long-range performance since the 1930s, when Lapua developed a special bullet with rebated boat tail designed to give Maxim belt-fed machine guns unprecedented accuracy at ranges of 1,500 meters and beyond, while minimizing barrel erosion commonly associated with boat tail bullets of conventional design. The resulting precision D46 and D47 bullets delivered a lot of gold medals in national, world, and Olympic championships. The new .338 LAPUA Magnum ball round features a novel bullet design based upon that heritage. The B408 Lock Base bullet features much more robust construction and a conspicuously shorter rebated boat tail, which is also distinguished by a slightly pointed base. The B408 Lock Base provides superior accuracy at long range while delivering a flat trajectory. Lapua offers a broad range of tactical and sporting rounds for the .338 LAPUA Magnum, and it would be useful to take a brief look at each of these different rounds.
Ammunition Selection It should come as no surprise that Lapua offers the largest selection of factory ammunition being produced for the .338 LAPUA Magnum. All variants feature a brass case and noncorrosive boxer primer, and are suitable for barrels with a 1 turn in 10 inch or 1 in 12 inch twist rate. .338 Lock Base (be = 0.662) The patented design of the Lock Base bullet enables the base of the projectile to tolerate higher velocities and chamber pressures that would deform the base of conventional bullets and therefore degrade accuracy. The rebated boat tail greatly reduces drag and provides a flatter trajectory than flat-based ball. This is the best choice for military applications and long-range target shooting. I should note this bullet design is also available in 7.62x51 mm ammunition featuring either 150 grain (9.7 gram) or 170 grain (11 gram) projectiles. .338 Scenar (be = 0.675) The Scenar bullet is a match-grade, hollow point boat tail design that is suitable for long-range target shooting as well as for law-enforcement applications. The HPBT projectile weighs 250 grains (16.2 grams), and its low-drag design gives it an excellent ballistic coefficient. Scenar ammunition is also noteworthy for its consist quality from one box to another. The Scenar bullet design is also available in 7.62x51 mm ammunition In three bullet weights: 155 grain (10 gram), 168 grain (10.9 gram), and 185 grain (12 gram) as well as respective moly-coated Silver Jacket Scenars. .338 FOREX (be = 0.229) For hunting big or dangerous game, Lapua recently introduced the FOREX soft point hollow base rotating bands bullet that features an ingenious hollow rear chamber, which puts the projectile's center of gravity forward of geometric center. This gives the SPHBR projectile much better, arrow-like stability when encountering objects in the bullet path, and this design also provides flatter trajectory. The FOREX projectile features CNC-machined construction that includes narrow driving bands to engage the rifling with minimum bore wear. Nammo Lapua Oy also makes cal .338 AP-bullets as well as star-crimped blanks and dummy steel inert training rounds for the .338 LAPUA Magnum. Figures 1 and 2 compare bullet velocities and trajectories of the .338 LAPUA Magnum 250 grain (16.25 gram) FMJ B408 Lock Base, with White Feather 7.62x51 mm 175 gr (1 1.38 gram) FMJ BT, and Remington .300 Winchester Magnum 190 gr (12.35 gram) FMJ BT out to 1,500 yards. Since the .338 is also intended to perform in an anti-materiel role, momentum is compared in Figure 3. These data will give a sense for intrinsic capabilities of these three sniping calibers. Hands-On Performance Perhaps the most noteworthy aspect of the Erma's design is that it features quick-change barrels in .308 Winchester, .300 Winchester Magnum, and .338 LAPUA Magnum. The German counter-terrorist teams GSG-9 and KSK adopted the SR 100 in .338 LAPUA Magnum. Clearly, the versatile Erma SR 100 has some interesting potential for military, law enforcement, and advanced sporting applications. Shooting the Erma rifle proved addictive for two reasons: (1) the accuracy it delivered, and (2) the human engineering that went into the rifle.' The muzzle brake was particularly effective. The .338 LAPUA Magnum kicked like a .308 fitted with a sound suppressor, and the .308 kicked like a .223 rifle. But it is the accuracy delivered by the Erma that really makes the SR 100 interesting. Using a Nightforce Mil-Dot 5.5-22x56 rifle scope, it is easy to shoot 3/8 to 1/2 MOA groups at 200 yards (183 meters) until the wind picked up. The Nightforce optics were wonderfully bright and sharp, enabling you to see .338 caliber bullet holes clearly at 200 yards.
ERMA SR 100 cal. .338 LAPUA Magnum featuring a paratrooper-length fluted barrel and a Nightforce Mil-Dot 5.5-22 x 56 rifle scope. The Erma SR 100 Precision Rifle is a very interesting and a very versatile system, featuring kits that enable the operator to change calibers in the time it would take to change shoes. Quick-mounts enable swapping day and night optics without the loss of zero. When employed with the .338 LAPUA Magnum kit, the Erma SR 100 can solve problems nearly a mile away (1.5 kilometers or 0.9 mile). This system provides a mix of capabilities that can satisfy a wide range of missions. Only accurate rifles are interesting, and this is the most interesting rifle I've ever used. The Erma also demonstrates that the .338 LAPUA Magnum offers compelling performance for military snipers and law-enforcement special response teams, as well as for civilian target shooters and big-game hunters. The .338 LAPUA Magnum has earned the respect of advanced military and civilian shooters, and this impressive round should become increasingly popular in the 21st century.
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RWS 6x68s RIFLE CARTRIDGE The 8 x 68 S rifle cartridge (the S stands for Spitz and also means it is intended for 8.2 mm (.323 in) groove diameter bullets) and its necked down sister cartridge the 6.5 x 68 (no S or anything else required) were developed in the 1930-ties by Mr. Schüler from the August Schüler Waffenfabrik, Suhl, Germany as a magnum hunting cartridges that would just fit and function in standard sized Mauser 98 bolt action rifles. This is one of the early examples where a de novo rifle cartridge (the 8 x 68 S and 6.5 x 68 has no other parent cartridge case) was developed by a gunsmith to fit a specific popular and widespread type of rifle. |
 | 8 x 68 S (1939) |
| 6.5 x 68 (1939) |
| .375 Hölderlin (2007) |
Standard military 7.92x57 mm Mauser 98(k) rifles have to be adapted by a competent gunsmith to function properly with these magnum cartridges since they are longer and the cases have a larger diameter then 7.92x57 mm Mauser cartridges. The 7.92x57 mm Mauser cartridge is also known as the 8 mm Mauser or in Germany as the 8x57 IS (IS stands for Infantrie Spitz). In adapted standard military Mauser 98k rifles the large 8 x 68 S cartridges are well known for 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 Mauser 98 bolt action rifles makes the shorter 8 x 68 S, 6.5 x 68 and .375 Hölderlin interesting chambering options.
World War 2 spoiled the commercial introduction and spread of the 8 x 68 S amongst German hunters. The cartridge because of its high performance and flat trajectory became popular after Word War 2 when German hunters were allowed again to own and hunt with full bore rifles. The 8 x 68 S performance made hunters who had problems with handling magnum cartridge recoil use a less powerful but adequate medium cartridges like the 7.92x57 mm Mauser, 7 x 64 (Brenneke) or .30-06 Springfield (also know as the 7.62 x 63 in metric countries). Recoil sensitive shooters can fit an efficient muzzle brake to significantly reduce the amount of recoil. With the help of a muzzle brake the 8 x 68 S recoil is reduced to tolerable levels.
Extremely thick brass results in only 5.584 ml (86.0 grains) water case capacity for the 8 x 68 S. A rare feature of this German rimless bottlenecked centerfire cartridge design is that it has a slightly rebated rim (P1-R1 = 0.3 mm). A sign of the era in which the 8 x 68 S was developed are the gently sloped shoulders. The exterior shape of the case was designed to promote reliable case feeding and extraction in bolt action rifles, under extreme conditions.
8 x 68 S maximum cartridge dimensions. All sizes in millimeters (mm). Americans would define the shoulder angle at alpha/2 ≈ 14.53 degrees. The common rifling twist rate for this cartridge is 280 mm (1 in 11.02 in), 4 grooves, Ø lands = 7.89 mm, Ø grooves = 8.20 mm and the primer type is large rifle.
According to the CIP (Commission Internationale Permanente Pour L'Epreuve Des Armes A Feu Portative) guidelines the 8 x 68 S case can handle up to 440 MPa (63817 psi) piezo pressure. In CIP regulated countries every rifle cartridge combo has to be proofed at 125% of this maximum CIP pressure to certify for sale to consumers.
The American .325 WSM cartridge introduced in 2005 is probably the closest ballistic twin of the 8 x 68 S. The .325 WSM is considerably shorter and fatter and has a more radical rebated rim (P1-R1 = 0.51 mm), much steeper shoulder angle (70 degrees / 35 degrees for Americans) and a shorter neck (7.82 mm). This makes the 8 x 68 S case with its 9.11 mm long neck better suited for loading long heavier bullets and due to its sleeker exterior shape will cycle more readily in bolt action rifles under extreme conditions.
German big game hunters often use 8 x 68 S rifles in Africa for hunting plains game, where American hunters would choose one of the .30 or .338 magnum cartridges. The 8 x 68 Sis a civil cartridge that can be used in countries which ban civil use of former or current military ammunition.
Since there are few factory loads readily available (RWS offers 2 factory loads) and due to its good field reputation and efficiency, the 8 x 68 S is often used by reloaders. They have used this cartridge extensively to create powerful loads by handloading. Whilst staying within the 440 MPa CIP limit a 8 x 68 S rifle with a 650 mm (25.59 in) long barrel and appropriate modern gunpowder (Vihtavuori N560) can be handloaded to propel a 12.96 gram (200 gr) 8 mm bullet like the Sierra MatchKing to a muzzle velocity of 927 m/s (3042 ft/s).
Maximum muzzle velocity comparison in % of the probably most proliferated European and American 8 mm rifle cartridges out of 650 mm (25.59 in) long barrels loaded with relatively light to heavy 8 mm bullets to their CIP or SAAMI (Sporting Arms and Ammunition Manufacturers’ Institute) sanctioned maximum pressures.
| Bullet weight (grains) | (127 gr) | (150 gr) | (175 gr) | (200 gr) | (220 gr) | Case capacity (%) |
| 7.92x57 mm Mauser (8 x 57 IS) | 100.00 | 100.00 | 100.00 | 100.00 | 100.00 | 100.00 |
| .325 WSM | 108.67 | 109.12 | 109.01 | 109.30 | 111.14 | 131.73 |
| 8 x 68 S | 108.38 | 108.50 | 108.68 | 110.49 | 112.27 | 136.49 |
| 8 mm Rem. Mag. | 111.89 | 112.33 | 114.46 | 115.26 | 116.02 | 157.13 |
This comparison is not totally objective since the 8 mm Remington Magnum and .325 WSM operate at 448.16 MPa (65000 psi), the 8 x 68 S at 440 MPa (58740 psi) and the 7.92x57 mm Mauser at 390 MPa (56564 psi) maximum chamber pressure. Higher chamber pressure results in higher muzzle velocities.
The 8 x 68 S has a good long range accuracy reputation i.e. it is not hard to develop or find loads that will shoot 1 MoA or better out of good standard mass produced rifles. Factory 8 x 68 S rifles often have a 650 mm or 26 in barrel with a 280 mm (1 in 11 in) twist rate, which works well . This twist rate was chosen since the bullet jackets used in 1930 were not strong enough to cope with the forces generated by the magnum muzzle velocities of the 8 x 68 S. The 240 mm (1 in 9.45 in) twist rate normally found in the 7.92x57 mm Mauser makes the 8 x 68 S combined with modern bullets with jackets designed for magnum cartridges an awesome long range cartridge.
Reloaders use the 8 x 68 S as a Jack of all trades cartridge on all European game from fox, roe deer and chamois upwards to the big European game like red deer, moose and brown bear. Reloaders realized that bullets with different characteristics can be utilized to produce varying effects on game. They also realized that from 8 mm calibre upwards the rise of sectional density and penetrating capability of practical spin stabilized rifle bullets (bullets up to 5 to 5.5 calibres in length) tends to flatten out.
This means that loaded with light, short and soft nosed 8 mm bullets the 8 x 68 S can be used on small game. Loaded with heavy, long and hard (solid copper) bullets the 8 x 68 S offers enough speed derived power to penetrate heavy and dangerous game. The 8 x 68 S is suitable for hunting almost any game animal on the planet, though certain sub-saharan Africa countries have a 9.53 mm (.375 in) minimum calibre rule for hunting Big Five game - i.e. leopard, lion, cape buffalo, rhino and elephant. In the Central African Republic, where there are no ammunition limits for hunting Big Five game, the 8 x 68 S has been used successfully for hunting elephant.
The 8 x 68 S case has functioned as the parent case for the .375 Hölderlin (9.5 x 68), which is essentially a 9.525 mm (.375 calibre) necked-up version of the 8 x 68 S. The wildcat status of the .375 Hölderlin ended in 2007 when it got CIP certification and became an officially registered and sanctioned member of the German 68 mm family of magnum rifle cartridges. If the .375 Hölderlin becomes available as factory ammunition, like the older cartridge (8 x 68 S and 6.5 x 68), is still unknown.
.375 Hölderlin maximum cartridge dimensions. All sizes in millimeters (mm). Americans would define the shoulder angle at alpha/2 ≈ 14.53 degrees. The common rifling twist rate for this cartridge is 305 mm (1 in 12 in), 6 grooves, Ø lands = 9.30 mm, Ø grooves = 9.55 mm, using a large rifle primer.
The .375 Hölderlin has 5.65 ml (87.02 grains) water case capacity. According to the official CIP guidelines the .375 Hölderlin case can handle up to 440 MPa (63,816 psi) piezo pressure.
According to the creator of the .375 Hölderlin, Mr. C. Otterbein, the idea behind the .375 Hölderlin was to develop a big game cartridge based on a German cartridge case for standard sized Mauser 98 bolt action a competent gunsmith can relatively easily rechamber a standard Mauser 98 rifle to accept 8 x 68 S based cartridges.
Cartridges that are not officially registered with, nor sanctioned by CIP (Commission Internationale Permanente Pour L'Epreuve Des Armes A Feu Portative) or its American equivalent, SAAMI (Sporting Arms and Ammunition Manufacturers’ Institute) are generally known as wildcats. 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 on the parent cartridge case, wildcatters may also change the original calibre. A reason to change the original calibre 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 CIP 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 8 x 68 S 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 8 x 68 S as the parent case wildcatters have created .25 x 68, .270 x 68, 7 x 68, .30 x 68, .338 x 68, .375 x 68 or .416 x 68 variants. Improved or blown out 68 mm cartridge designs are reported to come performance wise close to the 8 mm Remington Magnum which has about 14% more case capacity then the standard 8 x 68 S.
Examples of 8 x 68 S based wildcats are the relatively well known American 7 mm and .30 caliber Boo Boo and 7 mm and .30 HV wildcats. The Boo Boo wildcats were developed for long range target shooting where participants usually handload their ammunition. Several 1,000 yard shooting competitions have been won with Boo Boo wildcats. A wildcat from Europe that uses the 8 x 68 S as its parent case is the .30 Kovacs. It was designed in 1996 by Stefan Kovács. The .30 Kovacs has much more powder capacity (longer L2, wider P2, 40 degree Ackley-shoulder) then its parental case. It falls powder capacity wise between the .300 Winchester Magnum and .300 Wby. Mag. but has energy and velocity falling between .300 Weatherby Magnum and the .300 Remington Ultra Magnum.
Extremely thick-walled brass results in a 7.402 ml (114.0 grains) H2O cartridge case capacity for the .338 Lapua Magnum. The exterior shape of the case was designed to promote reliable feeding and extraction in bolt action rifles.
.338 Lapua Magnum maximum cartridge dimensions. All sizes in millimetres (mm). Americans would define the shoulder angle at alpha/2 ≈ 20 degrees. The common rifling twist rate for this cartridge is 254 mm (1 in 10 in), 6 grooves, Ø lands = 8.38 mm, Ø grooves = 8.58 mm and the primer type is large rifle magnum.
According to the official CIP guidelines the .338 Lapua Magnum case can handle up to 420 MPa (60,915 psi) piezo pressure. In CIP regulated countries every rifle cartridge combination has to be proofed at 125% of this maximum CIP pressure to certify for sale to consumers.
The American .338-378 Weatherby Magnum cartridge introduced in 1998 is probably the closest currently commercially available ballistic twin of the .338 Lapua Magnum. The .338-378 Weatherby Magnum is unfortunately a belted cartridge.
For a typical .338 Lapua Magnum military sniper rifle like the Sako TRG-42 with a 690 mm (27.17 inch) long 1 in 12 inch rifling twist rate barrel at sea level, 1500 meters (1647 yards) is considered to be the maximum shooting distance for man sized targets when using standard Lapua military loads. The 16.2 gram (250 gr) Lapua Scenar bullet (G1 BC = 0.675), for which the TRG-42 was optimized, has a supersonic range of 1500 meters under warm summer conditions at a muzzle velocity of 915 m/s (3002 ft/s). However, to be able to maintain over 90% hit probability on non-moving targets, this maximum shooting distance has to be reduced to 1300 meters (1422 yards) at freezing point conditions or 1100 meters (1312 yards) in arctic winter conditions, when the muzzle velocity may drop to 880 m/s (2887 ft/s). Only during optimal warm summer conditions (muzzle velocity increases up to 915 m/s (3002 ft/s)) is the maximum shooting distance of 1500 meters (1647 yards) is realistically achievable.
Loaded with more aerodynamic .338 calibre bullets than the ones Lapua uses such as the Sierra Match King .338 19.44 gram (300 gr) bullet (G1 BC ≈ 0.768) or the Lost River Ballistics J40 .338 17.5 gram (270 gr) CNC manufactured mono-metal bullet (G1 BC = 0.871) the long-range performance and maximum range of .338 Lapua Magnum rifles can be extended. These longer Very Low Drag bullets require a 1 in 10 inch twist rate to stabilize them. The .338 17.5 gram Lost River Ballistic Technologies J40 match bullet (G1 BC = 0.871) is one of the most aerodynamic .338 calibre bullets available. It has a 1829 meters (2000 yards) supersonic range under optimal warm summer conditions at a muzzle velocity of 869 m/s (2850 ft/s). This makes engaging static targets up to 1800 meters (1969 yards) feasible.
Improvement beyond this standard while still using standard .338 Lapua Magnum brass is possible, but the bullets have to be very long and the normal cartridge overall length of 93.5 mm has to be exceeded. The common 1:10 inch rifling twist rate also has to be tightened to stabilize very long projectiles. Such commercially non-existent cartridges are termed "wildcats". The use of a wildcat .338 Lapua Magnum based cartridge demands the use of a custom or customized rifle with an appropriately cut chamber and a fast-twist bore. An example of such a special .338 calibre extreme range bullet is the German CNC manufactured mono-metal 18.92 gram (292 gr) LM-105 (G1 BC ≈ 1.133 – this Ballistic coefficient (BC) is calculated by its designer, Mr. Lutz Möller, and not proven by Doppler radar measurements). The LM-105 bullet has an overall length of 54.79 mm (2.157 in) and derives its exceptional low drag from a radical LD Haack or Sears-Haack profile in the bullet's nose area . Rifles chambered for this wildcat cartridge, with a cartridge overall length of 105 mm (4.13 in), and equipped with custom made 1:7 inch progressive twist rate 900 mm (35.43 in) long barrels finished first and second at several long range competitions. It’s most recent win (2007) in an international Special Forces and police sniper competition in Switzerland was against rifles chambered for .308 Winchester up to .50 BMG at ranges from 100 m - 1500 m (109 yd – 1640 yd). The LM-105 bullet exhibited its very low wind drift susceptibility notably at ranges beyond 800 m (875 yd).
The commercially successful .338 Lapua Magnum cartridge has functioned as the parent case for the .300 Lapua Magnum, which is essentially a necked-down version of the .338 Lapua Magnum. The .338 cartridge case was used for this since it has the capability to operate with high chamber pressures which, combined with smaller and hence lighter bullets result in very high muzzle velocities.
The Finnish ammunition manufacturer Lapua got the .300 Lapua Magnum CIP certified, so it became an officially registered and sanctioned member of the Finnish "family" of super magnum rifle cartridges. The .300 Lapua Magnum is not commercially available and currently exists only as a CIP datasheet. It is however still used by a few shooters who produce the cases from .338 Lapua Magnum brass by reshaping the shoulder and neck, and handloading it with .30 calibre bullets.
The .300 Lapua Magnum has a 7.337 ml (113.0 grains) H2O cartridge case capacity. The exterior shape of the Lapua Magnum case was designed to promote reliable feeding and extraction in bolt action rifles .
.300 Lapua Magnum maximum cartridge dimensions. All sizes in millimetres (mm). Americans would define the shoulder angle at alpha/2 ≈ 25 degrees. The common rifling twist rate for this cartridge is 240 mm (1 in 9.45 in), 4 grooves, Ø lands = 7.62 mm, Ø grooves = 7.82 mm and the primer type is large rifle magnum.
According to the official CIP guidelines the .300 Lapua Magnum case can handle up to 470 MPa (68,167 psi) piezo pressure. In CIP regulated countries every rifle cartridge combination has to be proofed at 125% of this maximum CIP pressure to certify for sale to consumers.
This is for rifles with very high maximum chamber pressures, the cases of the .300 and .338 Lapua Magnum are built to cope with this. The large bolt face combined with the high 470 MPa (68,167psi) maximum pressure makes that the .300 Lapua Magnum should only be chambered in rifles that are capable of handling such large and fierce cartridges and high bolt thrust safely. Chambering such powerful super magnum cartridges in rifles intended for normal magnum rifle cartridges and using 470 MPa (68,167 psi) loads can cause serious or fatal injury to the shooter and bystanders.
The .338 Lapua Magnum case is also used as the parent case for a host of modified variants that neither are officially registered with and sanctioned by CIP nor its American equivalent, SAAMI. Such cartridges which use commercial factory cases are generally know as wildcats. 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 are often marginal. Besides changing the shape and internal volume of the parent cartridge case, wildcatters also can change the original calibre. A reason to change the original calibre can be to comply with a minimal permitted calibre or bullet weight for the legal hunting of certain species of game. Because the .338 Lapua offers a large and exceptionally sturdy, pressure resistant cartridge case that can be relatively easily reloaded and hence be reused several times it has become quite popular amongst wildcatters. With the .338 Lapua Magnum as the parent case wildcatters have created 7 mm (7 mm Katzmeier), .30 (.30-338 Lapua (Triebel), .30 Wolf), 8 mm (8 mm-338 Lapua (Triebel), LM-101), .338 (.338 Yogi, LM-105), 9.3 mm (9,3-338 Lapua Magnum (Triebel)) and .375 calibre variants.
