Myth Busting Big Game Calibers Optimum Big Game Calibers for each of 36 Hunting Scenarios based on a Renewed Understanding of Maximum Practical Shooting Distance I was contemplating the good and bad points among big game rifle calibers when I read Chuck Hawks article "Hunting Rifle Accuracy" and another by Wayne van Zwoll, "Reaching Out." They got me thinking. I came to the conclusion that my perception of a very important factor--practical big game hunting range--was flawed. How could I blame myself? Just look at Internet posts, gun magazines, ballistic tables, scope reticle designs, shooting books, advertisements, shooting DVD titles, etc. How could anyone not come to the conclusion that killing game over 300 yards is commonplace? I should have realized this long ago, based on 40+ years of shooting experience. Why didn’t I? I think it was a gradual media seduction, as well as my fascination for the subject. Of course, clean 300+ yard kills of big game animals do happen, but not nearly as often as you might think. Competitive bench rest shooters, F-Class Target shooters and military snipers can perform out to 1,000 yards and beyond, while specialized setups with shooting benches, wind socks, etc. can make hunting past 300 yards practical. However, there is a world of difference between these shooters, their equipment, their training and shooting conditions, compared to "Joe the Plumber" hunting white tails from a stalk, stand or a blind. After studying the matter in detail, I came to the conclusion that 300 yards is indeed the maximum practical distance that the majority of hunters should attempt shooting game. This is explained in detail below. Beyond this distance, the chances of either missing a game animal or inhumanely wounding it will increase dramatically. However, it doesn’t end there. Like a row of falling dominos, the 300 yard limit changed my perspective on many related matters. Because of this range limitation, this article will explain why trajectory and wind drift, among high intensity and magnum big game calibers, are virtually identical for practical purposes and therefore should normally not be factors for selecting a big game caliber. Instead, the optimum caliber and load should be based on the tradeoff between power and reasonable maximum game weight and the reasonable maximum shooting distance expected. I evaluated a dozen big game calibers, ranging in power from the .243 Winchester to the .338 Remington Ultra Mag. For each caliber, I compared the performance of the widest range of factory loads available, broken down by “use categories” and presented in several tables. The end products of this evaluation are: 1) a table which identifies the “optimum caliber and load” for each of 36 hunting scenarios; 2) a “versatility score” for each caliber based on its performance within the 36 scenarios; 3) an “efficiency factor” for each caliber based on its power/recoil ratio; and 4) a “natural progression” of the most optimal/efficient calibers based on increasing power levels. Although I was a bit surprised by my findings, after some thought they made perfect sense. However, every evaluation method has aspects that others will question and this article is no exception. I have tried to be as fair, objective and unbiased as possible, but there will always be room for improvement. Methods and Sources I wanted to evaluate a broad range of modern bolt action big game calibers suitable for “medium” (also known as Class 2 or CPX2) and/or “large” (also known as Class 3 or CPX3) game. To keep things manageable, I selected these 12 calibers: .243 Win, .260 Rem, .270 Win, .270 WSM, .280 Rem, 7mm Rem Mag, .308 Win, .30-06 Spr, .300 Win Mag, .300 RUM, .338 Win Mag and .338 RUM. There are, of course, other suitable calibers, but in most cases, they are similar to, or inbetween, those listed above. While only a dozen calibers were evaluated, most of my findings apply to all big game calibers. For each caliber, I selected representative factory loads that best fit each of the following four “use categories”:
Tables 1 through 4 present ballistic coefficients, muzzle velocities, recoil (8 pound rifle), and other ballistics data for each load evaluated. Table 1: Flattest Shooting Loads By Caliber (ranked by least hold-over at 300 yards)
Table 2: Maximum Power Loads By Caliber (ranked by highest OGW at 50 yards)
Table 3: Conventional/Typical Loads By Caliber (ranked by highest OGW at 300 yards)
Table 4: Lower Power Loads By Caliber (ranked by highest OGW at 200 yards)
Even though factory rounds do
not always reflect the full range of loads available for a caliber, there have
been major improvements over the years. For example, Light Magnum and High
Energy loads by Hornady and Federal produce ammunition with higher power levels
than can be duplicated by handloads for some calibers (example: 180 grain 30-06
at 2900 fps). At the other end of the spectrum, Managed Recoil and Low
Recoil rounds by Remington and Federal offer
medium game power at approximately half the recoil. Another reason for
limiting this evaluation to factory loads is practicality. It’s simpler to deal with factory loads than it is
to judge the optimum hand loads for each caliber. I used mainly Remington factory
load data for convenience (not because I think Remington is best) and
factory loads from Hornady and Federal when I found a load that better met the
criteria for a particular use category. For example, in the "Most
Powerful" load category, the 30-06 load with the highest OGW at 50 yards
was the Hornady Light Magnum load, which does not have a Remington equivalent. In
the "Lower Power" category,
I found representative factory loads for only seven of the twelve
calibers. I used the BigGameInfo.com calculator
for all of my ballistics calculations. Ballistic coefficients (BC) for
factory loads without published BC data were estimated by trial and error. I simply
played with the ballistics calculator until the BC matched published down range
ballistics for the load. Recoil was calculated from
10xShooters.com because this calculator adjusts for muzzle velocities above and
below 2,700 fps. To calculate recoil for factory loads, I estimate powder
weights from equivalent handloads using data from Hodgdon.com. Since I did not
know the specific powder type used for each factory load, I had to make
educated guesses on powder weights based on averaging. For a few factory
loads, equivalent handloading data could not be found, so I extrapolated to
estimate powder weights. In all cases, I assumed the total weight of the
rifle and scope to be 8 pounds. I assumed a zero of 250 yards for the Flattest Shooting category, a 230 yard zero for the Most Powerful and Conventional categories, and a 200 yard zero for the Lower Power category. In each category, the zero distance was established to optimize bullet trajectory in order to exploit the maximum point blank range (MPBR), thereby minimizing hold over and under. In this case, the MPBR was based on the bullet rising no more than 3 inches above the line of sight. A load’s power is typically measured by kinetic energy (in foot-pounds). From the hunter’s perspective, this measurements is somewhat vague, since it does not take into consideration the game animal hunted. As a result, for measurements of terminal power to kill game, I used the OGW formula. It is a more practical measurement of power because it considers both energy and momentum and relates them to game weight, in pounds. For example, if a load indicates a 600 pound OGW at 300 yards, it means that this load is capable of humanely killing a game animal that weighs 600 pounds out to a range of 300 yards, assuming that the bullet is of suitable type and construction and strikes the vitals. OGW's for all calibers and loads evaluated are presented in the data tables. OGW is only an approximately measurement of terminal power, but it is the best measurement I found that allows hunters to relate the power of their rifles to the real world. While OGWs for each load were
calculated based on bullet weight and terminal velocity, I did not take into
consideration bullet type and construction. Bullet type and construction are
important factors for ensuring adequate terminal performance, but it is a
complex and dynamic subject beyond the scope of this article. You can
refer to several other Guns and Shooting
Online articles (see the Rifle Information page) that discuss the strengths
and weaknesses of different bullet types. When hunting, be sure your bullet
type is appropriate for your game type and shooting distance. The Maximum Practical Hunting Distance for Big Game is Approximately 300 Yards Under ideal bench rest
conditions with very accurate production hunting rifles, the best accuracy most
shooters can consistently achieve is about one-inch groups at a 100-yards, or
approximately 1 minute of angle (1 MOA). Keep in mind we’re talking about
“deer hunting” rifles with scopes and with typical total weights between 7½ to
8½ pounds, not heavy barreled, finely turned and accessorized target, varmint
or sniper rifles. While some manufactures, such
as Weatherby, guarantee rifles that can shoot under 1 MOA, this guarantee is
based on shooting the right type of premium ammo. More importantly, it’s
not realistic to expect any of these rifles to shoot sub 1 MOA groups all of the time. Even if a rifle was capable of perfect accuracy (0 MOA), it’s unrealistic to expect that most shooters can consistently hold the rifle steady enough to achieve less than 1 MOA, except with the aid of the most sophisticated rifle rests. With the current trend toward higher recoiling rifles, resulting from new magnum calibers and lighter weight materials, most shooters will shoot less accurately due to increased recoil. Further, when you add environmental factors, such as changing wind speed and direction, it is unrealistic to expect big game rifles to shoot less than 1 MOA the majority of the time. While it is not unusual to shoot, for example, one or two ½ inch groups at the range with your big game rifle, larger group sizes are the norm. As an aside, shooters often
confuse “accuracy” with “precision.” For hunting, you need both. As
an example, if you shot a nice three-shot ¾-inch group at 100 yards (excellent
precision), but that group was 4 inches above your intended impact point (poor
accuracy), such shooting would be unsuitable for humanely hunting game. Thus,
one cannot rely on group size alone to determine the capability of their rifle
and scope to take game. When you move from the range to the field, things change. Several factors degrade accuracy that were of much less of a concern at the rifle range. These include:
When you consider the additive effects on accuracy from all of the above, you cannot expect to shoot as well in the field compared to the rifle range. It’s just not realistic. A skilled shooter with a 1 MOA rifle (as tested from a bench rest), might be able to deliver 2 MOA groups from unsupported field positions and most hunters will not be able to shoot that accurately. However, for the sake of argument, let's use 2 MOA to represent practical accuracy in the field. Let’s distinguish between shooting medium (CPX2) and large (CPX3) game. Medium game animals of North America include deer, caribou, pronghorn antelope, black bear, sheep, goats and feral hogs. Typical game weights vary from about 90 to 300 pounds, with vital heart/lung kill diameters varying from about 8 to 12 inches. I agree with Chuck Hawks’ recommendation in "Hunting Rifle Accuracy" that medium game hunters should have the equipment and skills to shoot into a 6-inch area. This rule seems reasonable because hunters must also contend with other changing variables, such as correctly interpreting the center point of the vitals while the animal is moving and often being presented a less than optimum shot-angle. A 6-inch circle happens to be 2 MOA at 300 yards. Therefore, with few exceptions, the maximum distance one should attempt shooting medium sized game is about 300 yards. This 2 MOA limit may bruise some shooter’s egos, but it is hard to argue with the reality of the above 10 factors, each contributing to poorer accuracy in the field. What about large game? Large game of North America include elk, moose, musk ox, bison, brown/grizzly bear and polar bear. Game weights vary from about 400 pounds (small) to 1,600 pounds (very large), with a few extremely large bears, moose and bison weighing as much as 1,700-2000 pounds. The heart/lung vital area for large game varies from about 15 to 20 inches. Since this “kill zone” is about twice that found on medium game, you might think that hunters should be able to hunt these giants at ranges beyond 300 yards. However, this is rarely practical. Let’s illustrate with a 400 yard shot at a large game animal that weighs 700 pounds. This weight represents a very large elk, a slightly larger than average moose, or an average brown bear or musk ox. Many hunting rifles do not have the necessary power to humanely kill at this distance. In addition, other factors make a humane kill on such an animal difficult, if not impractical. First, it is very difficult to accurately estimate long ranges in the field without a rangefinder. Second, the recoil of the .338 Remington Ultra Magnum (the most powerful caliber included here) is approximately 50 foot pounds or about 2 ½ times that of a .30-06. While many hunters may have the stamina to shoot rifles with this amount of recoil, few of them can do so without flinching. The slightest flinch will result in missing the vitals of even the largest elk at 400 yards. Third, trajectory and wind drift become a much greater problem at 400 yards than they are at 300 yards. Referring to Table 1, which presents the flattest shooting loads in each caliber, you can see large differences in trajectory and wind drift between 300 and 400 yards. The flattest shooting caliber and load I could find was the .300 RUM shooting a 150 grain bullet. (A bullet far from optimum for shooting elk.) Its trajectory is awesome. At 300 yards, the hold over (assuming a 250 yard zero) is only 2.6 inches. However, at 400 yards it increases to 11.2 inches. For 10 MPH wind drift, the .300 yard value is 5.4 inches, while at 400 yards it increases to 9.9 inches. The wind drift is usually the biggest challenge, since it can be extremely difficult to judge windage corrections at such long distances, especially over uneven and unfamiliar terrain. Thus, with few exceptions, 300 yards (more or less) is the practical and reasonable range limit, for both medium and large game. Table 5: Large Game Killing Power Range by Caliber (ranked by highest OGW at 50 yards)
Trajectory and Wind Drift among modern big game calibers are essentially the same Some readers may scoff at this claim, so let’s break it down. First, it assumes the maximum practical shooting range is 300 yards, as explained above. Second, it assumes a sight in zero of 230 to 250 yards for each caliber. This may seem too far to some, but it makes perfect sense if you plan to shoot game as far as 300 yards away and because the MPBR of each caliber evaluated is roughly 300 yards. Next, let’s compare the flattest shooting loads in each caliber, shown in Table 1. To be conservative, let’s compare the caliber with the flattest trajectory (.300 RUM) to the one with the least flat trajectory (.338 Win Mag). The difference in trajectory between these two extremes at 50, 100, 200 and 300 yards is +0.7, +1.1, +0.8 and -1.2-inches, respectively. From the perspective of the shooter, the difference in hold-over/under shooting either caliber is virtually unnoticeable at the longer ranges of 200 and 300 yards. For example, let’s assume you are about to shoot at an elk 300 yards away with the .300 RUM load listed here. You are probably looking through a 9-power scope, typical for big game rifles. At 300 yards and at 9-power magnification, the vital area is a tiny target. At this range, you know the rifle will shoot 2.6 inches low, so any hold-over you wish to make would be extremely slight. Now, assume you are making the same shot with the .338 Win Mag load listed here. In this case, you would want to hold 3.8 inches high. Do you really think, under field conditions, that you can adjust your hold from 2.6 inches high to 3.8 inches high, while looking at a target (perhaps a moving target) 300 yards away through a 9-power scope? The best you can probably do is hold what appears to be a “few inches” high or not hold-over at all. That’s all the precision you are likely to have under those conditions. Try it yourself. Any practical difference in
hold over/under would probably be noticed at the closer ranges, where the
shooter may have the visual acuity to distinguish, using the above caliber
comparison, between a 1.7 and 2.8 inch hold under at 100 yards. In this case,
assuming you are familiar with your load’s trajectory and you can judge
distances out to 100 yards, you can simply make the necessary hold under. However,
this 1.1 inch difference would probably make no difference in hitting the vitals
at 100 yards. The comparison between any other two calibers/loads listed on Table
1 will be even less significant than this “extreme” example. Using another
comparison from this table, the 7mm Rem
Mag is renowned for its flat trajectory, while the 308 Win is not. Yet,
the difference in hold at 50, 100, 200 and 300 yards is only +0.4, +0.6, +0.5,
and -0.7-inch, respectively! Similar small differences in trajectory will be
noticed if you compare the trajectories in the other use categories. See
Tables 2 through 4. Here is another way to illustrate the similarities in trajectory among these big game calibers. For the loads listed on Table 1, the bullets of each caliber will not rise further than about three inches above the line of sight out to 250 yards (the zero distance). This means that, for all the calibers evaluated, if you hold dead-on, you should theoretically be able to hit the vitals of a big game animal out to about 275 yards without any hold over/under adjustment for elevation. For this reason, trajectory should normally not be a significant factor when choosing a high intensity or magnum big game caliber, since they all shoot with similar flatness out to near the maximum practical shooting distance. However, what could possibly be a relevant factor in caliber selection is wind drift, although perhaps only marginally. As shown on Table 1, the maximum difference between 10 MPH wind drift values is between the .338 RUM and the .338 Win Mag. At 50, 100, 200 and 300 yards, these differences are 0.1, 0.3, 1.0, and 2.5-inch, respectively. This illustrates that, out to about 200 yards, the differences in wind drift among all 12 calibers is virtually negligible. After that, wind drift differences increase, yet are still relatively small. Considering that it is much more difficult to correct for wind drift at longer ranges than elevation, wind drift might be a factor worth considering in caliber selection if you anticipate making shots over 250 yards in areas noted for high or gusty winds. Ordinarily, however, wind drift should probably not be a factor in caliber selection. Caliber Selection should be based on Power, Recoil, Game Weight and Shooting Distance If trajectory and wind drift are usually not differentiating factors when choosing a big game caliber, then what is? The answer can be found in the tradeoffs between power and recoil in the context of maximum anticipated game weight and maximum anticipated shooting distance. Power (estimated in OGW pounds) and recoil (measured in foot-pounds) are presented for all the calibers and loads evaluated in Tables 1 through 4. Recoil detrimentally affects accuracy. As a result, recoil should be a major constraining factor when choosing a caliber and load, although too often it is not. A good discussion is presented in "Rifle Recoil" (see the Rifle Information page.) There is a general consensus among authorities that recoil over 20 foot pounds will cause most shooters to develop a flinch, while others believe this threshold is as little as 15 foot pounds. The slightest flinch will throw the 300 yard range limit “out the window,” as groups sizes will dramatically increase. Many shooters find it hard to admit that recoil, even moderate recoil in the 15 to 20 foot pound
range, affects their accuracy, as though doing so might raise questions about
their manhood. Shooters find many ways to rationalize keeping their recoil
sensitivity a secret. For example, they read that hunters don’t feel the
recoil when pulling the trigger on game because of their adrenaline-charged
excitement and so they assume they must not flinch. Unfortunately, the
shooter’s unconscious muscle memory will cause him to flinch in the field the
same way he flinches at the range. Such bad habits are very hard to
break. This fact alone may help explain why there are so many misses and
wounded animals when shots are taken at longer ranges. Among the Conventional Loads
(Table 3), only two calibers have recoil below the 15 to 20 pound range, based
on an eight pound rifle and scope. These are the .243 Win and .260 Rem. Only
two other calibers have recoil within the 15 to 20 foot pound range, the .308
Win and .270 Win. The remaining eight calibers have recoil above the 20
foot pound threshold, in some cases dramatically more. The .280 Rem and .30-06
are slightly more (about 21 foot pounds); the .270 WSM, 7mm Rem Mag and .300
Win Mag are noticeably more (26 to 31 foot pounds); the .338 Win Mag is still
greater (36 foot pounds); while the .300 and .338 Remington Ultra Mags are far greater (51 to 54 foot pounds). How does a hunter decide on a
caliber, either when making a hunting rifle purchase or determining which of
their existing rifles to take on a hunt? This decision should be based on
the answers to the following three questions: 1.
What is the largest game size (in pounds) I realistically expect to
shoot? 2.
What is the maximum practical distance I expect to shoot such game? 3. How much recoil can I tolerate before it affects my ability to hit this game’s vitals at this distance? Optimum Calibers & Loads for 36 Hunting Scenarios In order to help hunters
answer the above three questions, I developed Table 6. This table shows which
caliber and load results in the least recoil for a given game size and given
shooting distance, and hence, is optimum. Nine game weight classes and
four shooting distances are represented, collectively representing 36 distinct
hunting scenarios. The loads used to create this table are the same ones
listed in Tables 1 through 4. Table
6 also shows which calibers and loads came in second and third places within
each scenario. Any ties are also identified. Table 6: Optimum Calibers/Loads for 36 Hunting Scenarios
How to Use Table 6 Let’s assume you are planning
a hunt and your answers to Questions 1 and 2 (above) resulted in a 700 pound
game animal at 300 yards and your answer to Question 3 was "22 foot pounds
recoil." As shown on Table 6, the caliber and load with the least
recoil for this scenario is the .338 Win Mag with a conventional factory load. However, it has 36 foot pounds recoil
(8 pound rifle). This is far beyond your 22 foot pounds recoil limit. At this point you can lower your expectations, either by reducing the anticipated maximum shooting distance or the game size. In this case, if you decide that a 700 pound animal at 200 yards or a 600 pound animal at 300 yards is still a reasonable maximum, then your optimum caliber and load, in either case, would be the 30-06 with maximum power loads (27 foot pounds recoil). Since this is still above your recoil limit of 22 foot pounds, you might decide that a 600 pound animal at 200 yards or a 500 pound animal at 300 yards is still a reasonable maximum. In this case, a 308 Win with maximum power loads would be your optimum choice, since it has only 21 foot pounds of recoil. An alternate approach to the above problem is to use a rifle with greater total weight or a gas operated action, or both, in order to reduce recoil. For example, if one needed the power of a .338 Win Mag, but could only tolerate the recoil of a conventional power .30-06, then a relatively heavy semi-automatic rifle such as the gas operated Browning Safari Grade BAR in .338 Win Mag would be a reasonable solution. Table 6 shows an interesting pattern, in that certain calibers clearly stand out as being more optimal than others. Specifically:
Based on Table 6, the
succession of the most optimum big
game calibers, in order of increasing power, are .260 Rem, .308 Win, .30-06
and .338 Win Mag. Why is that? The main reason is that all four of
these calibers have loads with muzzle velocities between 2,600 and 3,000 fps
(with a few exceptions). This muzzle velocity results in relatively flat
trajectories out to about 300 yards. When muzzle velocities are less than
2,600 fps, both trajectory and power are detrimentally affected. In contrast,
as muzzle velocities exceed 3,000 fps, recoil increases disproportionately compared to power, resulting in increasingly less optimal calibers and
loads. Even though trajectories become flatter as muzzle velocities increase,
these flatter trajectories have no practical advantage out to 300 yards, as
explained in detail above. Versatility Scores for Big Game Calibers In an attempt to validate
Table 6 findings, I developed a scoring system to measure and rank the versatility
of each caliber, based on how often it was found to be optimum in each of the
36 scenarios. For each scenario, I gave a caliber three points if it came
in first, two points if it came in second and one point if it came in
third. If there was a tie, I gave each caliber its full points. The results of this analysis
are presented in Table 7. They reflect a pattern similar to that shown in Table
6, in that the four calibers found to be most optimum are also the most versatile. The
most versatile caliber is the .308 Win (63 points), followed by the .30-06 and .260
Rem with 44 and 43 points respectively, followed by the .338 Win Mag (27
points). All other calibers scored significantly less (1 to 20 points). Some may argue that this
scoring method does not really reflect versatility, because, for example, the .30-06
can be used in more hunting situations than the .308 Win. While I
completely agree, just because a caliber can be used in more scenarios, does
not mean it is optimum for those scenarios. If the criterion for
versatility was what can be used, then the .338 RUM would be the clear winner
because it is the only caliber evaluated which can humanely kill game in all 36 scenarios. However, because of
its severe recoil (54 foot pounds), few people would agree that the .338 RUM is
the most versatile big game caliber. If you can shoot a rifle with 21 to
27 foot pounds of recoil without flinching, then the .30-06 would arguably be a
more versatile rifle for you than the .308 Win. If you are like the
average shooter and recoil over 20 pounds can adversely affect your accuracy,
then the .308 Win is arguably the most versatile caliber for you. Efficiency Scores for Big Game Calibers As another comparison, I calculated the efficiency of each caliber by comparing its power level to its recoil. Calibers with less recoil relative to their power level are more efficient. For simplicity, I only considered the two conventional loads for each caliber. To calculate a load’s efficiency, I divided each load’s OWG power level at 100 yards (considered an average shooting distance) by its recoil. To arrive at the efficiency value for each caliber, I averaged the efficiency values of both conventional loads for that caliber. The results are shown on Table 7 and indicate that the four most efficient calibers are the same ones found to be most optimum and versatile, .308 Win (37.9 points), .338 Win Mag (36.3 points), .30-06 (36.0 points) and .260 Rem (33.8 points). The other eight calibers scored lower. Seven of them are similar in efficiency and fall in the 29.5 to 31.0 point range, while the .300 RUM is the least efficient of all, scoring only 25.2. Table 7: Versatility and Efficiency scores by caliber (ranked by Versatility Score)
Conclusions The above analyses show the same four calibers to be the most optimum, versatile and efficient. The logical succession of these big game calibers, in order of increasing power, is .260 Rem, .308 Win, .30-06 and .338 Win Mag. One reason why the .260 Rem scored so well was because of the recently introduced “Managed Recoil” load from Remington, which has a 140 grain bullet with a muzzle velocity of 2360 fps and 9 foot-pounds recoil. This load won five of the scenarios for “up to 200 pounds” and “300 pounds” game weight classes. This load does not have the muzzle velocity to be useful out to 300 yards, but out to 200 yards it’s great. The 260 Rem has very similar ballistics and recoil as the more popular 7mm-08 Rem. The 7mm-08 Rem also has a “Managed Recoil” load with almost identical ballistics. Both of these calibers are arguably the best “deer cartridges” (medium game), especially when shooting at longer ranges, which stretch the capabilities of the far more popular 30-30 Winchester. (I would include the older, but very efficient, 6.5x55 and 7x57 in that conclusion. -Ed.) Competing medium game calibers not evaluated, such as the .240 Wby Mag and .257 Wby Mag, have muzzle velocities far greater than 3,000 fps and would be expected to have more recoil relative to their killing power. The .25-06 Rem, by comparison, is expected to be somewhere inbetween these Weatherby Magnums and the .260 Rem/7mm 08 Rem in terms of versatility and efficiency. The .308 Win and .30-06 scored especially well. This is because their muzzle velocities are in the 2,600 to 3,000 fps “sweet spot” and due to the diversity of useful loads. Their good performance in the Maximum Power and Flattest Shooting categories, for example, is a result of Light Magnum and High Energy factory loads. In Table 2, the Maximum Power load for the .30-06 has significantly more power at all ranges, with less recoil, than the Maximum Power load for the 7mm Rem Mag and the Maximum Power load for the .308 Win has significantly more power at all ranges, with less recoil, than the Maximum Power load for the .270 Win. Based on scoring, the .308 Win is the most optimal, versatile and efficient big game caliber. This contradicts the conventional wisdom that the .30-06 holds that title. However, if you can tolerate higher levels of recoil (in the mid-20’s foot pounds) without it degrading your accuracy, then the .30-06 is indeed the most versatile big game caliber for you. The .338 Win Mag is the “top dog” for heavy game. Its competitors, such as the .300 Win Mag, the two Remington Ultra Magnums and similar calibers, have excessive muzzle velocity--and hence recoil--relative to their killing power. This recoil results not only from the velocity of the bullet itself, but also the disproportionately large amounts of powder needed to propel projectiles at those velocities. The .338 Win Mag is a very efficient caliber in terms of its power/recoil ratio. If you can tolerate its recoil (36 to 43 foot-pounds) and muzzle blast, it is an excellent heavy game caliber. Some may wonder why the popular .270 Win, 7mm Rem Mag and .270 WSM did not have better showings. These calibers, along with similar calibers not evaluated (.264 Win Mag, .270 Wby Mag, 7mm WSM and 7mm Wby Mag) are optimally designed to take medium game at ranges beyond 300 yards. Since shooting game beyond this distance is rarely practical, the slightly flatter trajectories of these calibers results in disproportionately more recoil in relation to their power levels. |
Copyright 2009 by Greg R. Haskins. All rights reserved.