LJ Bonham is a semi-subsistence hunter, hunting magazine editor, and firearms enthusiast who lives in the Rocky Mountains.
Pronghorn. Antilocapra Americana. Speed Goat. Regardless the name, the world’s second fastest land mammal is a supreme challenge for even the most jaded hunter. These Pleistocene throwbacks can spot trouble miles away. Then they flee at 60 miles per hour into the next county.
The pronghorn’s primary habitat is open prairie and sage badlands. Some, however, inhabit forest margins and high altitude parks. I once observed a herd in Colorado at over 10,000 feet elevation. Minimal cover and long sight lines give a hunter little opportunity for close stalks, although I have used undulating terrain to get within 60 yards on several occasions. Most speed goats are taken at 200 to 400 yards, and many times beyond, through spot and stalk hunts. Shots from ground blinds are often inside 100 yards.
Pronghorn are amazing animals.
Two Cartridge Categories
Both the pronghorn’s eyesight and its environment conspire to make cartridge selection a much argued thing amongst speed goat hunters. Any center-fire rifle round, from .223 on up, will dispatch these nervous beasts, but some calibers have proven better over the years. Appropriate cartridges fall into two, general categories: standard rounds for shots inside 400 yards, and magnums for the longer stuff. However, there is considerable crossover in the range envelop. Several standards tested here tread close on the magnums’ heels and all the magnums will suffice in close with the right bullet. Magnums are also a good choice for mixed bag hunts which might include elk, moose, or mule deer as well as speed goat.
I chose six standard rounds and five magnums for comparison based on feedback from many veteran pronghorn hunters plus my own personal experience and preferences. Without a doubt, I have passed over someone’s favorite round, but article space precludes testing them all. Readers can extrapolate how their pet cartridge might perform by comparing it to a similar one in this test.
I picked rounds which represented particular caliber classes well. In this case, .24 (6mm), .25, .26 (6.5mm), .28 (7mm), and .30 (7.62mm). The standard cartridges in this shootout are: .243 Winchester, .25-06 Remington, 6.5 Creedmoor, 6.5-284 Norma, .270 Winchester, and .308 Winchester. The magnums are represented by the .240 Weatherby, .257 Weatherby, .264 Winchester Magnum, 7mm Remington Magnum, and .300 Winchester Magnum.
All were tested for trajectory, wind drift, effective range, and recoil with modern ballistic software available free online from shooterscalculator.com. Calculations were corrected to standard temperature (59F/15C) and pressure (29.92 inHg/1013 mbar) at sea level.
Trajectory in this test is defined as Maximum Point Blank Range (MPBR): the distance over which a bullet rises three inches above sight line and then drops three inches below to hit within a six-inch kill box, which is appropriate for the pronghorn’s stature. Imagine a bullet arcing through a six-inch diameter pipe for a certain distance and you have the idea.
For this test, drift is measured in inches from point of aim with a nominal 10 mph direct cross wind at 400 yards.
Effective range in this case is the minimum impact energy recommended for a humane kill on pronghorn-sized game (1200 ft-lbs.). Some writers claim as little as 800 ft-lbs. is sufficient, but I prefer a reasonable safety margin. Another factor is the minimum velocity most hunting bullets require for reliable expansion (1800 fps for standard bullets, 1300 fps for long-range bullets). If the minimum energy range exceeds the minimum expansion range, the minimum expansion range becomes the maximum effective range since unexpanded bullets are much less effective regardless how much energy they possess.
Recoil calculations were based on a modern, 8.0 pound synthetic-stocked, bolt-action rifle with scope. As a general rule, more than 15 ft-lbsf is considered enough recoil to affect most shooters’ accuracy. The less recoil, the more accurate the shooter, and hence, the more effective the cartridge.
Bullet construction and terminal performance are more important than caliber choice. Pronghorn are a bit smaller than whitetail deer. They weight around 80 -110 pounds, on average, although their leg and shoulder bones are quite heavy in proportion to take the stress induced when they dash around in rough country at high-speed. As a rule, bullets with fast expansion characteristics and high ballistic coefficients (BC), such as Nosler’s Ballistic Tip, Hornady’s SST, or Sierra’s Game King, are preferred. For long-range work, look to the newer low drag specialty bullets from Berger, Hornady, and Nosler, for example.
Tough bullets such as the Swift A-Frame or Federal’s Trophy Bonded Bear Claw are less desirable. A good compromise are controlled expansion projectiles in the Nosler Partition, Nosler AccuBond, or Woodleigh Weldcore class. These are the best choice for the magnums if closer shots are anticipated. Older designs like the Winchester Power Point, PPU Soft-Point, or Remington Core Lokt are also good, but they have low BC’s.
All calculations were based on the most suitable Nosler Ballistic Tip™ bullet unless otherwise noted. This is a good bullet for pronghorn-sized game and has the high BC needed for longer shots in windy conditions. Both BC and sectional density (SD) are noted for each bullet tested. BC quantifies a bullet’s aerodynamic efficiency, and SD predicts relative ability to penetrate into a game animal; the larger each number, the better. Most experts agree BCs around .450, or larger, make bullets fly flatter and drift less in cross-winds.
The magnums were tested with Nosler’s AccuBond Long Range (ABLR) bullet since their mission is more specialized and many hunters these days will choose a modern bullet made for the task. Muzzle velocities are the nominal industry standard for the tested bullet weight in each caliber for factory loaded ammunition to ensure standardization.
Note: Hand loaders can achieve much better performance in many instances.
Points were awarded as follows:
- One point for every 10 yards MPBR beyond 200 yards and one point deducted for every 10 yards less than 200.
- One point awarded for every inch less than 12 inches drift at 400 yards and one point deducted for every inch greater than 12.
- One point for every 25 yards beyond 200 yards for maximum effective range on medium game, and one point deducted for every 25 yards less than 200 yards.
- One point for every 25 yards beyond 200 yards for minimum expansion velocity, one point deducted for every 25 yards less.
- One point for each foot-pound recoil less than 15, and one point deducted for every ft-lbsf greater than 15.
Here’s how each cartridge ranked. Detailed performance figures are summarized in the table at the article’s end.
First Place: .264 Winchester Magnum, 63.6 Points
142 gr. AccuBond LR, .625 BC (G1)/.291 SD, 3000 fps. This particular Winchester magnum never gained a large following due in part to a reputation for premature barrel wear, but those who use it swear by it. It finished first among the magnums and overall because it has long legs, and balances power vs. recoil.
Second Place: 7mm Remington Magnum, 57.4 Points
168 gr. ABLR, .616 BC (G1)/.298 SD, 2900 fps. There’s been much written about the 7mm Rem. Mag. since its introduction in 1962, and with good reason. Its recoil is on the low end for a magnum. It fits into standard-length action sporter rifles. It’s a reliable hammer for game out to 600 yards and beyond. No wonder it is the best-selling hunting cartridge in the world and ammunition is available everywhere. If you could own just one rifle, a 7mm Rem. Mag. would serve you well no matter where you hunted.
Third Place: .300 Winchester Magnum, 53.5 Points
190 gr. ABLR, .597 BC (G1)/.286 SD, 2870 fps. There are harder hitting, more efficient, and longer ranged cartridges than the .300 Winchester Magnum, but few, if any, are available in almost any gun store around the world. For the one gun, international hunter, no other cartridge is as useful. Power, range, availability, flexibility, and accuracy; the .300 Winchester Magnum has done it all at reasonable cost, for more hunters, for over five decades. For those who think the .300 WM is too much for pronghorn, expert speed goat hunter, Bert Popowski, who wrote Hunting Pronghorn Antelope, often used, and liked, a .300 Weatherby which is more powerful than the Win. Mag.
Fourth Place: .257 Weatherby Magnum, 50.2 Points
115 gr. Ballistic Tip (ABLR unavailable in factory ammo), .453 BC/.249 SD, 3400 fps. The quarter-bore Weatherby is a phenomenon. Its laser-like trajectory makes it a great speed goat gun. While .25 caliber bullets don’t have sexy ballistic coefficients, the Weatherby zings them out so fast they get to the target before the wind has much chance to deflect them.
The .257 Weatherby hits way above its weight class
Fifth Place (Tie): .240 Weatherby Magnum, 42.8 Points and 6.5-284 Norma, 42.8 Points
.240 Weatherby: 100 gr. Partition, .384 BC/.242 SD, 3406 fps. The .240 Weatherby will amaze even jaded hunters. Its extreme velocity punches far above its weight class. It has one severe limitation: ammunition is only available from Weatherby. If you fall in love with this diminutive hammer, plan to load your own.
6.5-284 Norma: 140 gr. Ballistic Tip, .509 BC/.287 SD, 2875 fps. Like the 6.5 Creedmoor, the 6.5-284 Norma debuted as a precision target cartridge. Hunters soon discovered its effectiveness and it has grown in popularity since. It outperforms its closest competitors, the 6.5 Creedmoor and the newer 6.5 PRC, due to greater case volume.
Sixth Place: .25-06 Remington, 39.7 Points
115 gr. Ballistic Tip, .453 BC/.249 SD, 3060 fps. The .25-06 wins a real world trifecta. It is the lowest recoiling, flattest shooting, hardest hitting cartridge in existence. Although, for some inexplicable reason, it has lost market share over the last decade. Low recoil makes it a natural for novice and recoil sensitive shooters, or anyone who understands lower recoil means more accurate shots.
Pronghorn and the .25-06: made for each other.
Seventh Place: .270 Winchester, 36.7 Points
130 gr. Ballistic Tip, .433 BC/.242 SD, 3060 fps. The .270 appeals to a certain hunter; one who understands the finer points about ballistics—one who appreciates balance. The .270 is to hunting cartridges what the Porsche 911 is to cars: focused, precise, controlled, and when needed, violent and powerful. Its greatest proponent, Outdoor Life writer, Jack O’Connor, preferred 130 grain bullets for pronghorn, deer, and his beloved big horn sheep.
Eighth Place: 6.5 Creedmoor, 33.4 Points
140 gr. Ballistic Tip, .509 BC/.287 SD, 2700 fps. If you follow hunting guns and ammunition, you’d think the world had just scrapped every cartridge which doesn’t have the name “Creedmoor.” The 6.5 Creedmoor’s sole original mission: make tight groups on paper targets all day long. Despite the hype, it is a good big game round used inside its performance envelop, and a top pick for speed goat.
Ninth Place: .308 Winchester, 29.1 Points
165 gr. Ballistic Tip, .475 BC/.248 SD, 2700 fps. Developed from the .300 Savage in 1952 for use in the then new, M-14 service rifle, the .308 has gone on to become the most popular hunting cartridge in the USA. It is outsold elsewhere in the world only by the 7mm Remington Magnum and the .30-06. The .308 is versatile, performs close to the .30-06, and is available even in remote places such as Alaska and Africa.
Tenth Place: .243 Winchester, 29.0 Points
95 gr. Ballistic Tip, .379 BC/.230 SD, 3030 fps. Anyone who thinks the .243 Winchester will die any time soon will have to wait a long time. The rifles chambered for it number in the millions, and ammunition is plentiful and cheap. Many a novice hunter has taken their first pronghorn with the mild, accurate .243. It’s also used by experienced hunters who appreciate this dual purpose cartridge’s virtues. Despite last place in this test, the .243 is still among the best pronghorn rounds in existence.
What did we learn? Foremost we learned there are many excellent speed goat cartridges in the world. Regardless their score in this test, any here--in steady hands--will do the job just fine. There are also quite a few rounds not mentioned which hunters have used, or can use, for pronghorn; everything from the mild .30-30 Winchester or the venerable .45-70, to the safari grade .375 H&H. It all comes down to engagement range, bullet choice, and shot placement.
My choice? Most, if not all, my hunts are mixed bag affairs, and pronghorn is just one item on a menu which often includes elk, mule deer, and bear. I rely on a .300 Win. Mag. in the open country speed goats prefer. It has the reach if needed and the punch for the bigger critters. Loaded with a good, controlled expansion bullet in the 180 - 200 grain range, it has always proved a reliable companion. Given I also use safari caliber rifles often, the .300's recoil is a non-factor--for me (your mileage may differ). If I were after just pronghorn, in all likelihood I'd go with either the 6.5-284 Norma (sorry, Creedmoor fan boys) or .25-06 Remington.
Pronghorn Cartridge Test Results
|Cartridge||MPBR (yds)||Drift @ 400 yds (inches)||Effective Range (yds)||Expansion Range (yds)||Recoil (ft-lbsf)|
.264 Win. Mag.
7mm Rem. Mag
.300 Win. Mag.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
Questions & Answers
Question: Why did you leave out the .280 Remington cartridge?
Answer: It wasn't my desire, believe me. I love the .280, it is perhaps the best 7mm cartridge in existence. However, for article length considerations I had to keep things focused on the more popular cartridges, and the sad fact is the excellent .280 is ignored by the marketplace for the most part. Although, a small cadre of dedicated .280 shooters out there keep ammo sales limping along at a slow if steady, rate. As I said in the piece, I undoubtedly left out many people's favorite rounds, but such is the nature of gun writing. Glad you enjoyed the article.
© 2018 LJ Bonham