.338 Lapua Magnum

History

 
During the 1980’s a .338 caliber sniper cartridge appeared, sometimes referred to as the mystery sniping cartridge (Gun Digest 1986). Later it would be officially adopted by Lapua as the .338 Lapua Magnum or 8.6x70mm. Although the history of this cartridge was at one time difficult to uncover, today, the development of the .338 Lapua can be traced to its most likely beginnings.
 
At around the beginning of the 1960’s the U.S gun making firm Champlin Haskins Firearms developed a three locking lug magnum sized bolt action. Once the action design was realized,  Doug Champlin and Jerry Haskins consulted with U.S gun writer Elmer Keith as to what cartridge (and other features) he would find desirable in a magnum bolt action hunting firearm for use on large North American game.  Following this, Keith and fellow enthusiast Bob Thompson became involved in the development of a .338” caliber wildcat cartridge based on the .378 Weatherby case but shortened by a quarter of an inch to suit the powders of the day. It is worth noting that the .378 Weatherby was originally based on the .416 Rigby case but with the addition of a belt among other changes.
 
During the period of 1981-82, Jerry Haskins became involved in the development of sniper rifles for military use. These would be purpose built from the ground up and the resulting sleek minimalist designs were designated RAP 300 and RAP 500. RAP stood for the company name- Research Armament Prototypes however this name was later changed to Research Armament Industries (RAI). The RAP/RAI model 500 was chambered in .50BMG, a forerunner to modern .50BMG sniper rifle designs. The RAP/RAI 300 was a convertible switch bolt/barrel rifle initially chambered in .300 Winchester Magnum.
 
In 1983, RAI set about creating a .338 caliber cartridge for military use which would offer more penetrative power than the .300 Winchester but less recoil and more portability than the .50 BMG. The initial cartridge design was based on the .338-378 Weatherby wildcat however the U.S military were not interested in this design.  Following this, RAI developed a .338 Wildcat  based more simply on the 416 Rigby case necked down to .338” without the addition of a belt. 
 
Unofficial sources state that in 1983 the U.S Navy special forces bought some 125 RAP/RAI 300 .338 caliber rifles as well as the same number in .50BMG. Brass was manufactured by the company Brass Extrusion Laboratories while FMJ 250 grain projectiles were produced by Hornady.
 
Unfortunately, the BELL brass used for the production of the .338-416 could not reliably handle the pressures generated when loaded to launch a 250 grain bullet at the Military’s desired velocity of 3000fps. When RAI approached Lapua during 1984, Lapua engineers were only able to achieve high velocities at high pressure. To achieve the desired result the case walls had to be thickened at the web area to withstand high pressures. By 1985, Lapua had produced their first batch of ammunition.  The new case had slightly less capacity but gave good results firing the 250 grain bullet at 2950fps at a pressure of 61,000psi. The Lapua designation for the design was 8.6x71mm.
 
Still the military remained unhappy with the .338-416, more so now that its ammunition was made by a foreign entity.  At this point (1986), the concept of .338 magnum for military use was put aside. The cartridge had certainly obtained some mystique by this point as a result of ongoing developments including success within certain shooting competitions however this did little to help RAI. The failure to secure a military  contract was simply too much for RAI to cope with after so much financial commitment. RAI was eventually bought out by Daisy Defence systems which was then bought by Iver Johnson and later absorbed by AMAC - American military Armament Corporation.   
 
As for the orphaned .338-416, Lapua adopted the cartridge as its own in 1987 after making a few final tweaks. The final designation was 8.6x70mm or what we now know as the .338 Lapua Magnum.

 

The New Zealand connection

 
As of 1987, Lapua began to advertise 8.6x70 brass as becoming available but to countries outside of Europe. Nevertheless, the cartridge remained mostly unknown. When New Zealand Rod and Rifle Magazine’s Technical editor Graeme Henry visited the Lapua factory in the late eighties, Lapua Engineers had built a 338 Lapua magnum test rifle based on a Weatherby action fitted with a heavy magna ported barrel. Henry had been interested in the mystery cartridge for some time and was fortunate enough to fire the test rifle. When Henry next met with Lapua’s export manager Horst Zimmerbauer in New Zealand, he enquired as to the progress of the  .338 Lapua as a sporting rifle chambering. Upon hearing that no further advances had been made, Henry offered to build a .338 Lapua with the help of NZ gunsmith Din Collings using a Brno magnum action, then test the performance of the .338 Lapua as a hunting cartridge.  Reaching an agreement, Zimmerbauer obtained chamber drawings for Henry and the project began. This would be the first time the .338 was put to use in a hunting situation.
 
Henry had just enough time to fine tune loads, take the rifle into the hills overnight, shoot two deer and take photos before Zimmerbauer and marketing Director Juha Mikkola arrived in NZ to follow Henry’s progress.  Within the time frame given, Henry had not been able to obtain a variety of .338” projectiles and was limited to developing one target load using the Lapua FMJ 250 grain Lockbase bullet and one hunting load using the Hornady 225 grain Interlock.
 
Henry’s loads were a shade lower in velocity than factory specifications. Best accuracy from his 26” braked barrel using H4831 and the 250 grain bullet was obtained at a velocity of 2900fps.  The 225 grain Hornady bullet gave best accuracy at a velocity of 2950fps.  During the Finn’s visit, Mikkola was able to shoot both goats and deer. Upon inspection of a Fallow buck shot at close range it was found that the 225 grain Interlock displayed full fragmentation and as can be expected, massive internal wounding after striking the buck’s onside shoulder bone. In this instance the bullet did not exit and the remaining bullet fragments were recovered under the offside skin. Not exactly the great penetration that one might expect from a .338 caliber bullet however it was still impressive performance and far better than a narrow wound that might have been produced using something much stouter.  
 
After the Finns returned home, Henry continued on with the .338 and eventually wrote about his experiences with the .338 Lapua in Rod and Rifle magazine Volume 9, No 5, 1988.  The following year, Frank Barnes included a note about Henry’s hand in the development of the .338 Lapua as a hunting cartridge in his book Cartridges of the world. At about the same time, the Finnish rifle manufacturing company Sako adopted the .338 Lapua as a chambering for the Hunter grade series of rifles. Accuracy International were the first to offer the .338 Lapua as standard chambering for their sniper rifles. Following this, Sako went on to offer the .338 as a chambering for their TRG rifle.  Since this time, the use the use of the .338 Lapua has become widespread.
 
Case rim diameter of the .338 Lapua is .588” (14.9mm), wider than standard sized magnums which typically run from .532” (13.5mm) to .534” (13.6mm). The Lapua case rim is only a fraction smaller than the parent .416 Rigby case at .590” (15mm) and slightly larger than the .378 Weatherby at .582” (14.75mm). 
 
Once a rifle has been built or adapted to suit the Lapua cartridge it can be re-barreled to other cartridges based on the Rigby case such as the .378 Weatherby but cannot be re-barreled to the more common magnum cartridges without replacing the bolt.  For most shooters this means that once a .338 Lapua rifle is either built or purchased, the rifle will be permanently chambered for this cartridge.
 
Presently, the .338 Lapua is immensely popular and is utilized by snipers, hunters and target shooters. As is typically the case, much of its civilian popularity primarily stems from those who also have a strong interest in military weapons as opposed to a purely hunting or competitive shooting based interest.  The Lapua case has also been utilized by Lapua staff as a parent case design for the creation of 9.3, .30 and (for those who really like short barrel life) 6.5 caliber Lapua Magums. However, rifles chambered for these are somewhat rare. There are also several privately designed wildcats based on the Lapua case.

 

Performance

As a military cartridge, the .338 Lapua achieves its criteria in that it can reach out long and breach through light material to destroy targets. The term ‘one mile’ is often bandied about in relation to this cartridge with regards to its reach however anyone who has regularly shot at one mile will know that when shooting this far, the environment and skill of the shooter are as much a factor as how far a cartridge can effectively reach. Therefore, while the Lapua does have great reach, to speak of it within the context of this article as being an ideal one mile rifle is about as useful as saying that the BC of a basketball is ideal for shooting hoops from center court.
 
To truly meet the .300 Winchester magnum and .50 BMG halfway would require the adoption of something akin to the .375 Snipe-Tac, boasting a very high case capacity, extreme BC’s along with a bore diameter that inherently displays a more dramatic change in terminal performance. Beyond such pontification and increased recoil, realistically, the usage of the .338 Lapua is a matter for those who use it directly and its merits should be weighed according to individual concerns and outcomes. The Lapua is not really all that much of an improvement over what can be done today with a .300 Winchester Magnum and as a testimony to this, a good many Snipers have in more recent times shown a preference for the old .300 despite whatever shortcomings are thrown at it. Still, the Lapua is a tried and true military workhorse, especially within the UK expeditionary forces. It has a heavy pay load and gets the job done.
 
As a civilian cartridge The .338 Lapua can be both a fad and a trap. One the one hand, it can shoot long without fuss but on the other hand, the rifles utilized can at times be altogether too heavy for the likes of mountain hunting where the hunter hopes also to carry home a good load of meat. Furthermore, it is quite common for men to romanticize the Lapua and its military usage to the point that critical factors such as bullet choice are put aside to the detriment of game.
 
On the other side of the coin, there are those who would suggest that the .338 Lapua is too much gun for light framed game, conjuring images of lightly built animals being evaporated as if to leave the hunter with nothing more to cook than perhaps the contents of a scrotum. This is also quite fantastical thinking. The .338 bore is not too much gun and again, results vary depending on bullet choice. If you have a .338 Lapua and want to hunt lean game with it - do so, you are not over gunned. There are no special prizes for using the smallest possible cartridge to get the job done. And if it rains upon your hunt, you can be assured that these are tears of joy from your friend Elmer Keith looking down upon you. 
 
The .338 bore has some wonderful projectile offerings however as mentioned it is important to match projectiles to the job at hand. BC is only one part of the picture and it is pointless being able to reach out yet not have a bullet capable of rendering a fast killing wound. The internet and many books are filled with big talk by men toting big .338 canons and it is very easy for the novice to become caught up in such hype. Here I would like to drive the point home to the novice, that the .338 bore does not contain magical killing qualities. Owning a .338 Lapua Magnum does not guarantee you any abilities to shoot like a pro regardless of how much tactical lingo of acronyms you know. The Lapua cannot in civilian hands, do anything that the .340 Weatherby or .338-378 has not already done for the past several decades.
 
To reiterate on points already covered within this .338 section (see .338 Winchester Magnum):
 
The .338 Lapua is capable of producing fast kills on both light through and large bodied game at high impact velocities.
 
Below 2600fps, the .338 bore loses the ability to create hydrostatic shock and can produce slow kills on both light and heavy game.
 
As velocity drops to 2400fps, wound channel diameters between the .338, .30’s and 8mm bores can be much the same.
 
Low velocity .338 bullets that strike in line or slightly forwards of the foreleg on game of all sizes have the potential to destroy large amounts of locomotive muscle and vital tissue to slow game down fast, often within 2-3 yards.
 
Low velocity bullets that strike behind the Foreleg into the rear lungs meet little resistance and cause relatively small wounds, sometimes allowing medium game (including large but lean bodied deer) to escape long distances.
 
With regards to bullet choice, many .338 caliber bullets feature tough jackets which can produce slow expansion and suffer energy retention on light framed game. If using a heavy for caliber .338 bullet on lean game, it must be extremely soft in order to kill quickly in a reliable manner. Otherwise, a lighter weight bullet should be chosen (suggest Hornady range).
 
The .338 bore cannot be considered flexible without attention to bullet design or care towards shot placement or wind drift. That said, new bullet designs including the 200 grain Hornady SST have added a great deal of flexibility to the .338’s. The .338 Rocky Mountain ULD bullets and A-Max maximize wounding potential of the .338 bore at low velocities on light through to Elk sized game species. 
 
On large heavy animals, traditional conventional soft point .338” projectiles generally produce poor performance.  Heavy premium bullets produce far superior performance, allowing the hunter to utilize forward chest shots for relatively fast kills if used at close ranges where energy is high.

 

Factory ammunition

Factory ammunition for the Lapua is not a standard off the shelf item in most countries and the most common loads come from the original manufacturer Lapua with agents currently established in several countries. Lapua produce four factory loads for the .338 however only one is intended for hunters.
 
Lapua’s general purpose anti personal load features the 250 grain FMJ Lockbase B408 bullet at 2950fps from a 26” barrel, the Lockbase has an extremely high BC of .662. A 250 grain armour piercing (AP) load accompanies the Lockbase, designated AP485.   Lapua list the AP485 as being capable of penetrating 15mm of mild steel at 500 metres. 
 
Lapua’s target/ competition load features their 250 grain Scenar HPBT bullet at 2970fps and like the Lockbase this bullet has a high BC of .675. This bullet is not ideally (reliably) suited to hunting due to its heavy jacket and narrow hollow point which can fail to expand if little resistance is met. The meplat of this bullet can obviously be modified however results (improvement) are still largely reliant of the bullet meeting a good deal of target resistance.  
 
Lapua now also heavy 300 grain military loads for the Lapua including the Scenar, Lockbase and AP, all loaded to velocities of 2720fps. Again, none of these are ideally suited to hunting.
 
For a time, Lapua’s sole hunting load featured the 275 grain Swift A-Frame at 2600fps. This has since been replaced by the 231grain Naturalis (round nose homogenous copper bullet) producing 3000fps. As can be expected, this tough bullet is best suited to use on larger bodied game out to moderate distances where impact velocities can be kept high. This is certainly no problem for Finnish hunters where traditional hunting ranges are generally less than 200 yards.
 
The good news for those who can afford it, is that Hornady now offer a range of .338 Lapua ammunition. Among these are two loads suitable for hunting which include the 250 grain Interlock at 2900fps and better still, the 285 grain ELD (A-MAX) at around 2700fps. While the Interlock bullet is a modest performer on larger bodied medium game, the ELD is to be considered optimal as an all-around hunting load for the Lapua, useful for both light and large bodied game out to truly long ranges. That said, few people will be able to afford the asking price.

 

Hand loading

Due to the cost of factory ammunition (and lack of availability), the .338 Lapua cartridge is generally seen as a hand loading proposition.
 
From a 26” barrel, factory velocities can be duplicated with hand loads but reloaders should not expect to achieve higher velocities due to the fact that factory ammunition is already loaded to high pressures of 61,000psi. The Lapua case gives good results with ultra slow burning powders in the 7828/ ADI2217 (H1000) range. Achievable velocities include 3150fps with 225 grain bullets, 2950 to 3000fps with 250 grain bullets, 2700 to 2750fps with the 285 grain A-MAX / ELD and velocities also of around 2700fps with 300 grain bullets. Again, these velocities are standard for 26” barrels. In more recent times, it has been a common practice to adopt longer barrels of 28 or 30” in length which boost velocities by up to 70 and 140fps respectively.
 
COAL’s for the Lapua can be very long. Factory loads for the Scenar are set at 93.5mm (3.681”) with the projectile well off the lands. British factory ammo has traditionally been set shorter at 91.5mm (3.6”) for the sake of the slightly shorter magazines that have been used in the original Accuracy International rifle. Max COAL’s for the sleekest of bullet designs can be as long as 96mm (3.78”) depending on the individual bullet design. This should give the reader some indication of what magazine lengths are required and potential bullet jump.
 
Due to the fact that this cartridge produces similar velocities to the .340 Weatherby, a selection of useful projectiles and a description of their performance on game is contained within that text. An overview of the .338 caliber for use on medium game is given in the .338 Winchester Magnum text and those considering using any of the .338’s on medium game are urged to read these as a foundation.
 
One of the downsides of the .338 Lapua is that the most popular projectiles also tend to be the very worst for clean killing at extended ranges. Tough jackets and small hollow points are the primary problems leading to potentially cruel slow killing wounds if shot placement is not exact combined with a lack of suitable target resistance. Unfortunately, a good number of shooters refuse to address this reality and instead follow the hype with a sheep like mentality. Please understand that hunting is different to target shooting or sniping or pretending to be a sniper. Please also keep in mind that any “good” results obtained with stout bullets used on game at 400 yards have no bearing on what can happen at truly long ranges.
 
The very best bullets for fast and clean long range killing with the Lapua include those made by Hornady including the A-MAX / ELD (the SST out to more moderate distances) and Rocky Mountain (see Rocky Mountain article). No doubt others will come to the fore in time but for now, these wide hollow point bullet designs have proven to the only reliable true long range killers across a wide range of body weights. This is based on my own vast testing combined with honest correspondents performing the same rigorous testing. These projectiles can tackle a wide range of game weights, often producing an audible “whock” on impact combined with wide wounding and deep penetration.
 
Those who are truly interested in just what this cartridge can do when it is utilized in an optimum manner are encouraged to read my book - The Practical Guide To Long Range Hunting Cartridges (and other books within this series). It is extremely important to understand that paper energy figures and statements such as “one mile” are meaningless if the shooter is not himself up to the task or his ammo is potentially cruel killing in its design.

 

Closing comments

The .338 certainly has an interesting history. At this time of writing, it is immensely popular among civilian long range hunters. Ironically,  there are many cartridges which shoot a good deal flatter, my own we creation is but one of them. However, what this cartridge offers is a heavy pay load; not for the sake of BC (as most people assume), but for the sake of penetration as it was designed. In hunting terms, this can allow us to use a bullet that sheds more weight for wide wounding, yet still retain a good deal of weight for penetration on large bodied game. Bullet weight can add a great deal of versatility to a cartridge. But it can also go terribly wrong if the hunter does not have a basic grasp of bullet performance.

The weight of .338 Lapua tactical rifles is also a concern. A heavy rifle is fine for fixed position work and where the hunter has access to a vehicle, but for those who climb far and high, a heavy tactical rifle can be a complete pain to work with. A great many .338 Lapua rifles end up being sold second hand for this very reason. As always, practical application must always be taken into consideration.
 

Suggested loads: .338 Lapua					Barrel length: 26”
No	ID		Sectional density	Ballistic coefficient	Observed  MV Fps	ME Ft-lb’s
1	HL	Hornady 225gr SST/IB	.281	.515	3150	4956
2	HL	250gr Rocky Mountain	.281	.846	2950	4830
3	HL/ FL	285gr Hornady A-MAX / ELD	.356	.820	2750	4785

 

Suggested sight settings and bullet paths
1	Yards	100	150	295	337	375	400
	Bt. path	+3	+3.7	0	-3	-6.6	-9.4
2	Yards	100	150	283	325	350	375	400
	Bt. path	+3	+3.7	0	-3	-5.2	-7.7	-10.5
3	Yards	100	257	300	325	350	375	400
	Bt. path	+3	0	-3	-5.6	-8.3	-11.4	-14.1

 

No	At yards	10mphXwind	Velocity	Ft-lb’s
1	300	5	2600	3398
2	300	3.3	2622	3815
3	300	3.7	2426	3724

 

 

.338 Lapua	Imperial	Metric
A	.588	14.93
B	.587	14.91
C	20 Deg
D	.544	13.82
E	.370	9.41
F	2.161	54.9
G	.327	8.31
H	2.724	69.2
Max Case	2.724	69.2
Trim length	2.714	68.9

 


The .338 Rocky Mountain ULD produces excellent low velocity wounding without need of a great deal of target resistance.

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