September 23, 2010
Ten chamberings that can really go the distance.
For decades, when military marksmen and snipers needed to engage targets at long range they used the same cartridges as normal infantrymen. Ballistics of these rounds, whether German, American, British, Russian, French or Chinese, were all very similar.
Most of the major powers issued rounds driving bullets between .308 and .323 inch in diameter and weighing from 150 to 198 grains. A few countries, notably Japan, Italy, the Netherlands and Sweden, issued smaller caliber 6.5mm cartridges. Velocity of all these loads ranged from 2,350 fps to 2,900 fps depending upon barrel length and the individual load.
While some shot a bit flatter than others, the differences between them out to 800 yards was relatively small. With the possible exception of Sweden's 6.5x55, none really stood out from the crowd when fired from a rifle.
Shortly after the end of World War II many of the traditional military rifle cartridges disappeared from the inventory of the major powers. These were replaced by the new 7.62 NATO in the West and the 7.62x54R in the East.
These two cartridges became the primary long-range cartridges for snipers on both sides of the former Iron Curtain and are the benchmark by which other cartridges are measured today. In actuality, neither of these is ideal for dedicated use at long range, so I thought it would be interesting to take a look at the benchmarks and some of the other choices available today.
Despite looking like an archaic dinosaur, the ancient "54R" is actually well-respected among European competitive riflemen. Dating from 1891, this tapered, rimmed cartridge has proven to be surprisingly accurate in a quality bolt-action rifle, but it falls short in performance.
Typical old-school Russian match loads push a 200-grain FMJ-BT projectile at approximately 2,500 fps. Newer match loads, such as from Sellier & Bellot and Black Hills, drive Sierra's 174-grain MatchKing at around 2,600 fps. The current Russian military 7N14 sniper load pushes a 152-grain bullet at 2,723 fps.
All of these loads are at their best under field conditions inside of 800 meters, and while it has proven effective in Iraq and will be with us for years to come, the 54R is less than ideal for use at long range.
The current U.S. Army 7.62x51 sniper load is the M118LR (Long Range). It drives a 175-grain Sierra MatchKing at approximately 2,600 fps. Ballistic coefficient of this projectile at that velocity is approximately .496. While an accurate load, drop and wind deflection are less than ideal.
To get the most out of this cartridge, many competitors at sniper-type matches switch to a lighter 155-grain Lapua Scenar. This projectile has a BC of .508 and performs very well when driven at around 2,850 fps. Both drop and wind deflection are noticeably decreased: 20 inches less drop at 600 yards and 83 inches less drop at 1,000.
Even tweaked, though, this cartridge is still not ideal for use past 800 meters, although it can get the job done.
6.5x55 Swedish Mauser
Developed the same year as the 7.62x54R, the 6.5x55 Swedish Mauser is still popular in Scandinavia for long-range shooting. A couple years ago I attended Lapua's annual sniper competition in Finland where I saw a number of European competitors using 6.5x55 Sig Sauer sniper rifles to good effect out to 1,000 meters.
It is capable of driving bullets with relatively high ballistic coefficients at respectable velocities with excellent accuracy, mild recoil and acceptable barrel life. A modern rifle can safely drive a 139-grain Lapua Scenar (.615 BC) at 2,850 fps--providing a whopping 116 inches less drop and 33 inches less wind deflection (full value 10 mph crosswind) at 1,000 yards than the .308 M118LR load.
Sgt. Dustin Chisholm holds his Barrett sniper rifle after a patrol in Iraq. Soldiers have a love/hate relationship with the big .50 and feel its role is limited.
Performance falls off quickly after 1,100 yards, though, and the cartridge is cursed by dimensions that mandate a long action--although the large case allows it to handle long, high-BC 6.5mm bullets without eating into case capacity. While largely ignored here in the US, the 6.5x55 is an excellent 1,000-yard cartridge.
The .260 Remington is one reason why the 6.5x55 is largely ignored today. Long available as wildcat cartridge, the .260 was standardized by Remington in 1997. The cartridge itself is basically a .308 Winchester necked down to .264 inch.
Long-range performance almost but not quite duplicates modern 6.5x55 loadings in a short-action compatible cartridge.
Like all cartridges firing .264 inch projectiles, the .260 excels when fed high-BC match bullets--the Sierra 142 grain MatchKing (.595 BC) or Berger 140-grain VLD (.640 BC) to name just two. These efficient projectiles make the diminutive .260 Remington an honest 1,000-yard cartridge and one capable of outstanding accuracy.
Is the .260 perfect? No. Those long, high-BC bullets cut into case capacity. That said, the .260 Remington is an excellent cartridge for the rifleman taking long shots under true field conditions. Brass is readily available, thanks to its .308 Winchester parent case. Recoil is mild and barrel life is relatively good. Many long-range shooters who previously lugged .308s now carry .260s. For use out to 1,000 yards, it's an excellent choice.
One newcomer that shows promise is Hornady's new 6.5mm Creedmoor. Introduced in 2007, this cartridge was developed by Dave Emary and Joe Thielen of Hornady. Using input from two-time national champion Dennis DeMille, they pushed the shoulder back on a .30 TC and necked it down to 6.5mm.
Designed from the ground up for competition, this cartridge offers performance similar to the .260 Remington, but with its longer neck and slightly shorter case length (1.915 inches), bullets do not intrude on powder capacity like with the .260. Water capacity runs 51 to 52 grains.
Hornady's goal with this cartridge was for it to be not only extremely accurate but capable of driving high-BC bullets at respectable velocity with decent barrel life. Hornady's factory loads co
nsist of a 140-grain A-Max (.585 BC) at 2,810 fps and a 120-grain A-Max (.465 BC) at 2,980 fps.
Offering performance on par with the .260 Remington, the Creedmoor outperforms both the .308 Winchester and 54R at distance, but it's still relatively new, so there's only one source for brass right now. We will just have to wait to see if it catches on.
Based upon the .284 Winchester, the 6.5-284 Norma offers a big step up in performance from the .308 and .260 rounds. Submitted to Commission Internationale Permanente (the European equivalent of SAAMI) in 1999, this cartridge is merely a .284 Winchester necked down to take .264-inch bullets. Case capacity is an impressive 68.3 grains of water.
A well-respected 1,000-yard cartridge, the 6.5-284 Norma is capable of driving a 142-grain MatchKing at 3,000 fps. The result is a flat trajectory and relatively little wind drift compared to our two benchmark cartridges. The 6.5-284 easily outperforms the best .308 Winchester and 54R loads a handloader can cook up. It does this partially through the use of very efficient projectiles with high BCs and partly through old-fashioned raw horsepower.
Accuracy is also excellent, and the cartridge has taken its share of titles and trophies in competition. And while it can stand toe to toe with the .300 Winchester Magnum on the 1,000-yard line, it does so with noticeably less recoil, and in the hands of a highly skilled marksman, it can reach out to 1,200 yards. Even at this long distance it is still packing more than 700 ft.-lbs. of energy.
Although 6.5mm cartridges -- (l.-r.) 6.5-284 Norma, .260 Remington and 6.5mm Creedmoor -- have never caught on with mainstream Americans, they're excellent choices for long-range use.
As good as the 6.5-284 Norma is, though, it does have an Achilles heel. All that performance comes at the price of very short barrel life. It's not uncommon for barrels subjected to heavy loads to suffer severe throat erosion after only 1,500 rounds.
7mm Rem. Mag.
Long the darling of Secret Service marksmen, this belted magnum dates from around 1962. Not as popular as it once was, the old "7 Mag" is still an excellent long-range cartridge.
Based on the .375 H&H Magnum, with a case length of 2.5 inches and an overall length of 3.29 inches, the 7mm Remington Magnum is truly in the magnum class. It's able to drive, for example, a 162-grain A-Max (.625 BC) at 3,000 fps, producing a 246-inch drop and just 55 inches of wind drift (full value, 10 mph) at 1,000 yards.
Accuracy of a properly built 7mm Remington Magnum is excellent, and recoil is quite tolerable. Like the 6.5-284 Norma, though, the downside is short barrel life. Although short and fat magnums have become the rage in the last few years, the 7mm Remington Magnum remains one to consider for use out to 1,200 yards.
.300 Win. Mag.
Introduced in 1963, the .300 Winchester Magnum has proven very effective in long-range competition and on the battlefield. Accurate and far reaching, the big "Win Mag" has long been the darling of 1,000-yard competition shooters. It performs extremely well and is capable of excellent accuracy at 1,000 yards.
Regarding military use, the Navy began playing with the .300 Winchester Magnum decades ago. The service wanted to extend the range of its snipers by giving them something with more "zing" than a .308 was capable of but without the signature and size of the .50 BMG.
The Navy originally began using a 185-grain Lapua FMJ-BT but eventually switched to a 190-grain Sierra MatchKing. Target velocity was 2,950 fps. During development of what came to be known as the A191 load, much work was done on the chamber design (headspacing off the shoulder, not the belt), and the result of this work is a flat-shooting and hard-hitting 1,200-yard cartridge. The downside to the .300 Winchester Magnum is heavier recoil and a relatively short barrel life--1,500 to 2,000 rounds.
Despite these drawbacks, the .300 Winchester Magnum is very popular with the U.S. military units fielding it. Although Sierra's 190-grain MatchKing (.533 BC) remains the standard, there are projectiles available with much higher BCs if you are willing to go up in weight. All in all, the big Win Mag is an excellent cartridge well-suited to long-range use.
.338 Lapua Magnum
Developed from the ground up for long-range sniping, the .338 Lapua Magnum by all accounts performs superbly. It dates back to the early 1980s and the CIA's covert war against the Soviets in Afghanistan. The military wanted a long-range cartridge capable of penetrating five layers of Kevlar at 1,500 yards--something with more reach than a .300 Winchester Magnum but more portable than a .50.
Developers Jerry Haskins, James J. Bell and Boots Obermeyer turned to the .416 Basic case as a starting point, redesigning it and necking it down to take a novel 250-grain .338 projectile designed by Hornady. When funding ran out here in the U.S., Lapua redesigned and refined the cartridge into what we know today as the .338 Lapua Magnum.
The cartridge is impressive in both dimension and performance. Base diameter is .587 inch, case length is 2.72 inches and overall length is 3.68 inches. Performance-wise, the .338 Lapua will drive a 250-grain Lapua Scenar at 2,950 fps and a 300-grain Sierra MatchKing at 2,850 fps.
While the 7.62mm NATO and 54R work well out to 800 yards, higher BC projectiles or more horsepower will making hitting easier at longer range: (l.-r.) 7.62x54R, 6.5x55, 7.62 NATO, .300 Winchester Magnum, .338 Lapua Magnum.
With a BC of .768, the MatchKing still has more than 1,300 ft.-lbs. of energy at 1,500 yards. This load drops 730 inches and drifts 118 inches in a full value 10 mph wind at 1,500 yards. I have heard of some very skilled riflemen taking this cartridge out past 2,000 yards. Plus, unlike the previously mentioned cartridges, the .338 Lapua Magnum has some anti-materiel capability.
Downside is greater muzzle blast, heavier recoil and increased weight. If you want to reach past 1,200 yards, though, the .338 Lapua Magnum is hard to beat.
The big dog on the block for Western cartridges is the .50 Browning Machine Gun cartridge. Based upon the .30-06 but enlarged in a ratio of 5:3, it was obviously developed as a heavy machine gun cartridge, but chambered in either self-loading or bolt action rifles, the .50 BMG has proven useful for sniping and anti-materiel and explosive-disposal work.
The biggest drawback to using this cartridge in a rifle is the relatively poor accuracy of the standard M33 ball, M8 API and M20 APIT ammunition. If available, the specialized Mark 211 Mod 0 "Raufoss" round offers a step up in accuracy. This load drives a 671-grain projectile at a little over 2,700 fps from a Barrett M82A1.
Despite its performance, the big Barrett gets mixed reviews by U.S. soldiers for anti-personnel use, and most feel the round is best reserved for anti-materiel work.
Teamed with an accurate rifle such as this Canadian PGW, the .338 Lapua Magnum offers impressive exterior and terminal ballistics.