The Super .338 Magnums (.338 A-Square, .338 Excaliber, .338 Lapua, 8.59mm Titan and .338-378 Wby.)

By Chuck Hawks

What I am calling the "Super .338 Magnums" are a series of .338 caliber 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 Magnum

The .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 commercialized 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.

I have seen reloading data that 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 Magnum

As 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 Titan

Lazzeroni 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-Square

The .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.


Reloading 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."

Back to the Rifle Information Page

Copyright 2003, 2010 by Chuck Hawks. All rights reserved.