Is the .308 a Viable Long Range Cartridge?
Everyone seems to be talking (and writing) about "long range" hunting these days, so I guess I'll join the fray.
Most of the purpose-built rifles for hunting at extended ranges resemble military sniper rifles in size, weight and configuration: heavy-taper barrels, McMillan tactical stocks, bipods, oversized scopes with lots of magnification and target knobsâ€”the works.
Most rifles that come in such a configuration from the factory seem to be chambered in .308 Winchester, which begs the question of whether this cartridge is up to the task of taking game at long range.
If we're going to answer this question, we must begin by clarifying our definitions. "Long range" means different things to different people, in different parts of the country. For the sake of this discussion, let's assume that long range hunting begins at 300 yards and goes out from there.
I'm not saying I agree with the ethics of taking long shots at unwounded game for the sake of it, I don'tâ€”I'm just going to tell you whether the equipment will get it done if you can. I think this is valuable information for a variety of reasons, the foremost of which is that if I wound an animal and my only opportunity for a follow-up shot is at long range, I want to be able to put the animal down for good.
There are four relevant factors in determining whether a cartridge is viable for long-range hunting: trajectory, wind drift, impact velocity, and accuracy.
Trajectory is less important than it once was thanks to the widespread availability of laser rangefinders and scopes with bullet drop reticles and external adjustment knobs, but we still want the flattest bullet flight that we can get.
Nosler's loading data for the .308 shows that a 165-grain Accubond bullet can reach a muzzle velocity of 2,820 feet per second (fps) with a max load of RL 15. At sea level, using a 200 yard zero, that projectile will drop 76 inches at 600 yards, which means 12 MOA of "come up." While dialing for 76 inches of drop is not a big chore using target knobs, it would be pretty well impossible to do with any precision using a standard reticle and no means of making field adjustments.
For comparison's sake, if we use an Accubond of similar sectional density, the 6.5-284 Norma's 130-grain Nosler drops about a foot less at the same distance. That's not a huge difference, but as the range increases, so does the disparity in bullet drop. Out at 900 yards, the .308 drops 30 inches more than the 6.5-284.
The Norma cartridge will fit on the same action length as the .308 so we are really comparing apples to apples here.
With wind speed and direction being equal, how much a bullet is affected by wind is a function of bullet construction (BC, weight, etc.) and flight timeâ€”the longer a bullet is in the air, the more time wind has a chance to have its way with it.
This time lets compare the .308 to a cartridge that uses the same parent caseâ€”the .260 Remington. With a 140-grain Accubond at 2,820 fps in a 10 mph full-value wind, the .260's shot will drift 86.5 inches at 1,000 yards.
Bullet velocity being equal, the .308 drifts only about 9 inches further in the same wind. Not bad.
When we're talking about hunting, the bullet can't just hit the animalâ€”it must hit the animal with sufficient speed to expand the bullet and do the tissue damage necessary to put the animal down.
Nosler Partition and Accubond bullets are designed to expand at 1,900 fps or greater (most other bullet designs expand at similar velocities, but let's stick with our Accubond example for now). Our maximum effective range on game will be the distance at which the round crosses the 1,900 fps threshold.
Using Nosler data once again, we find that the 165-grain bullet falls below the velocity threshold at between 500 and 550 yards. The lighter 150-grain bullet is in the same ballpark at just over 500 yards, and the 180-grain falls below 1,900 fps at just over 400.
Here's where the capability of the cartridge runs into a wall of factsâ€”no ballistic computer or high-dollar optic is going to make that bullet expand. Are there bullets on the market that will perform at velocities under 1,900 fps? I'm sure there are, but none that I'm aware of advertise the fact.
If we're talking about shooting game animals at long distances, we need a cartridge and rifle that are capable of consistently putting bullets into the vitals of our intended targets. Much has been written about the "inherent accuracy" of the .308 Winchester, and I actually buy into this.
That doesn't mean that every .308 will shoot MOA or better, but most rifles so-chambered have behaved well on the range for me.
Even with a gun that shoots 1.5 MOA, we're still talking 7.5 inches at the 500-yard mark where we cross below our velocity thresholdâ€”that's plenty of accuracy to get the job done on most big game animals.
The .308 Winchester is capable of the mechanical accuracy, trajectory, and wind resistance in order to make hits on big game animals at far beyond the ranges at which I intend on shooting them. Where we hit a non-negotiable barrier is the velocity threshold necessary for reliable bullet performance. In most bullet weights, that distance is around 500 yards at sea level.
From an ethical standpoint, I cannot recommend using a cartridge at distances where the bullet cannot be counted on to do its job. I'd call the .308 an adequate cartridge out to 500 yards, but beyond that you'll need to show me a bullet that will perform well at that distance.
Before you say it, yes, I am aware that the .308 has done decades of duty as the go-to sniper rifle cartridge for our military. That doesn't mean that it was the best tool for the job, and it doesn't mean that it's a great choice for shooting deer at 700 yards.
Burris Eliminator III
An on-board ballistics calculator removes much of the necessary math, making this a great everyman long distance scope. Just zero at 100 yards, plug in the specs of your ammo, including the ballistic coefficient, sight-in distance and drop value, press a button to engage the built-in 1,200-yard laser range finder and wait for the appropriate dot in the X96 reticle to light up.
The Eliminator III
also has a built-in hold-off calculator for a 10 mph wind value. The battery lasts up to 5,000 cycles and the scope comes with a 40 minute-of-angle adjustment range and a 1/8 MOA click value.
Available with four illuminated front focal plane reticle styles (Mil4, Mil6, MSR/Ki and AMR), the Kahles 6-24x56 scope
is designed specifically for long range shooting. The scope is built on a 34mm tube and comes with .1 mil impact correction per click.
The parallax is adjustable from 50 yards to infinity. The K624i weighs 33.5 ounces and is 15.9 inches. The eye relief is 3.54 inches.
Leupold Mark 4 ER/T
has been in the scope business for decades and the quality of their products reflects the company's history. The Mark 4
series is an example of Leupold's dedication to that quality. The 4.5-14x50 has 70 MOA adjustment for elevation and windage and a front focal tactical milling reticle in a 30mm tube.
It's equipped with Leupold's exclusive Xtended Twilight Lens System, allowing shooters and hunters to stretch out their time on the range or in the field late into the evening. The Mark 4 ER/T also has a twin bias spring erector system, a locking eye piece and a 3-to-1 zoom ratio.
Zeiss Victory FL Diavari
Shooters who demand the highest quality scope will find plenty to like in the Zeiss Victory FL Diavari
series. The 4-16x50 is available with Zeiss' Rapid-Z ballistic reticle or the ASV bullet drop compensator reticle.
Illuminated reticles are also available. The Diavari is parallax-free at 55 yards to infinity and is built on a 30mm tube and comes with a .34-inch adjustment per click at 100 yards. It has a 3.54-inch eye relief and is just 13.24 inches in overall length. It weighs about 26 ounces.
Nikon Prostaff 5
Still dipping your toe into the long range shooting pool? No need to spend a month's salary, thanks to Nikon's Prostaff 5
line of scopes. The 4.5-18x40 has 40 MOA elevation adjustment, a1/8 MOA click value, instant zero-reset turrets, parallax adjustment and other features long-range shooters demand.
It also has high-quality glass and a mildot reticle to help you get on target at long ranges. Nikon's Prostaff 5 Series also includes Spot On Ballistic Match Technology, which allows you to calculate various aim points for various yardages for specific loads.
Serious long range shooters are fans of Nightforce
optics for good reason. Its ATACR
, short for Advanced Tactical Rifle scope, is the company's newest addition to its already-proven lineup of long range scopes. It's capable of 120 MOA/34.9 mils of elevation adjustment and a 60 MOA/17.45 mil wind adjustment and comes with Nightforce's ZeroStop technology.
That allows shooters to return to the zero with a few turns of a knob without fear of ever losing that zero. The ATACR has a 34mm tube and is just 14.3 inches long. It's available in three different reticles, including MOAR, MOAR-T and MIL-R.
Swarovski Z6 5-30x50 BT
There's good, better and best. And then there's Swarovski
. The name is synonymous with the highest standard in optics and the Z6 is as good a scope as you'll find. It's made with the best glass in the optics business.
The Z6 BT
(ballistic turret) has a maximum elevation adjustment of 43.2 inches per hundred yards and 1.2 inches per hundred yards of windage adjustment in a 30mm tube. The impact point correction is .36 inches per hundred yards. Parallax is laterally-adjustable beyond 55 yards with its own turret.
Trijicon earned the respect of soldiers on battlefields throughout the Middle East. The company also gained the respect of serious shooters, thanks to Trijicon's 3-15x50 TARS
, a long-range workhorse that performs as flawlessly as the guy behind the gun. It features a first focal plane reticle and 150 MOA/44 mil total elevation adjustment, 120 MOA/22 mil total windage adjustment and 30 MOA/10 mil adjustment per revolution.
The turrets also have locking devices to prevent accidental movement and the TARS features a return-to-zero setting. The illuminated reticle is available in four configurations and has 10 illumination settings, including two suitable for night-vision use.
US Optics LR-17
You may have never heard of US Optics
, but serious long range shooters are quite familiar with the company. The LR-17
is one reason. Adhering to the high standards 1,000-yard shooters demand, US Optics builds their scopes with the highest-quality glass and other materials.
It has a 74 MOA elevation range and a 64 MOA windage range and an adjustable magnification range of 3.2 to 17 power. Reticles are available in Mil, MOA and Horus options and all LR-17s include the company's unique Erector Repositioning Elevation Knob that maximizes gross elevation travel adjustment.
Vortex Viper HS LR
One of the few scopes designed for long range shooting that's priced under [imo-slideshow gallery=223],000, the Vortex Viper HS
is a great choice for shooters who want to ease into the thrilling world of long range shooting. It has many of the same features as top-end scopes at a fraction of the price.
The Viper LR
has a maximum elevation adjustment of 75 MOA and a max windage adjustment of 50 MOA and a parallax adjustment from 50 yards to infinity. The Viper HS features a second focal plane Dead-Hold BDC reticle and Customizable Rotational Stop turrets that allow a quick return to zero after a long day at the range. It weighs just 21.4 ounces and is 13.7 inches long.