March 05, 2014
One of the hallmarks of a great big game bullet is its ability to offer good terminal performance from very close range to long range. Almost any bullet can be made to expand at long range, but the thin jackets and soft cores that promote such expansion don't support bullet integrity when impact distances are close and velocities extremely high.
Conversely, it's not that difficult to produce a bullet that will hold together at close-range, high-impact velocities, but the heavy jackets, harder lead-alloy cores and bonding processes used to create such bullets can inhibit expansion when distances stretch and velocities drop.
It takes a lot of research and development and field research by a good team of engineers to design a bullet that will both expand and hold together through a wide range of velocities.
Granted, for 80 percent or more of the game (whitetails) shot by Americans, bullets don't really need to hold together and penetrate particularly deeply to provide clean, humane kills. Classic, soft, cup-and-core bullets perform beautifully on deer-size animals. They typically expand violently, causing tremendous wound cavities and resulting in rapid kills.
If they penetrate only 12 or 14 inches (inhibited by that same massive frontal diameter that's causing such dramatic tissue destruction), that's usually adequate. Heck, few whitetails, antelope, mule deer and even average black bears measure much more than 12 inches broadside through the vitals. It's when game such as elk, moose, caribou, mountain goats and the bigger bears are on the menu that bullet integrity becomes critical.
On such heavy-bodied game animals, which are challenging to hunt and rarely offer a perfect broadside presentation, I'm a believer in using premium, heavy-for-caliber bullets. They typically expand well through a wide velocity window yet hold together well for deep penetration on animals that measure 20 inches or more through the vitals- on a perfect broadside shot- and offer capable penetration if a quartering-to shoulder shot or a quartering-away raking shot is all that's offered.
How to choose one of the myriad premium bullets available today? To throw a little light on the subject (and out of my own curiosity), I recently shot a selection of eight of my favorite bullets into 10-percent gelatin at 50 and 400 yards. The results are chronicled and analyzed here, beginning with criteria.
It wasn't hard to choose a bullet diameter and weight and a cartridge through which to test it: America is still a .30 caliber nation; 180-grain projectiles typically offer excellent sectional density and ballistic efficiency; and the .300 Win. Mag. is both capable and popular, especially on the heavy-bodied game where bullet performance becomes critical.
As for distances, I'd already decided to choose 50 yards as the close mark, and after some discussion the editor settled on a max of 400 yards- a long shot, for sure, but a range at which most accomplished riflemen can make clean, ethical hits from field positions.
Most of the professional ballisticians I've spoken with agree that a projectile's rotational velocity has little effect on impact expansion. However, some point out that since rotational velocity maintains itself much longer than downrange velocity, it must, to some extent, affect expansion via centrifugal force.
Therefore, rather than simply loading down to simulate 400-yard impact velocities (which has the unavoidable side effect of reducing rotational velocity), we set gel blocks out at 400 yards and shot them.
The following photographs of our test subjects show an unfired bullet, a sectioned bullet and a bullet recovered from gel at 400 yards and a bullet recovered from gel at 50 yards. Take a look at the bullets themselves and what we learned. Data are also found in the accompanying charts.
Barnes Tipped Triple-Shock X
The only homogeneous bullet included in this test, the Barnes TTSX
was the first of its ilk and may still be the best. Constructed of solid copper, bullets in the X line are renowned for almost 100 percent weight retention. Grooves around the shank alleviate the original X's tendency to produce heavy copper fouling and also lessen bearing surface — enabling higher, more consistent velocities. A polymer tip was added about six years ago, which, to my mind, proved the perfecting element of an already great bullet by aiding aerodynamics and ensuring reliable, consistent expansion.
At 50 yards the TTSX I shot into gelatin expanded immediately and produced a dramatic, classic football-shaped temporary cavity (the really destructive path within the first foot or so of after-impact travel) and penetrated an admirable 27.5 inches. The recovered bullet averaged 0.66 inch of expansion, well over double its original diameter, and weighed 178.8 grains for 99.3 percent weight retention. In essence the bullet lost only the polymer tip. Great performance in every aspect.
Impact performance at 400 yards was similar, with the exception of somewhat less expansion (0.50 inch) and the expected deeper penetration allowed by the reduced frontal diameter. The TTSX surpassed the next deepest-penetrating bullet by 5.0 inches (roughly 15 percent). Weight retention was again 99 percent.
For steeply quartering-shot presentations that require deep penetration to reach the vitals, there is no better choice than the TTSX. It's also known for exceptional, forgiving accuracy.
Federal Trophy Bonded Tip
A unique crossover design featuring a solid copper base and a bonded, lead-core front half, the Federal Trophy Bonded Tip
is known for dramatic expansion coupled with the deep-penetrating characteristics of high weight retention. A boattail and a polymer tip aid aerodynamics; the tip also reduces the likelihood of deformation from recoil while in the magazine and during travel up the feed ramp into the chamber.
Penetration at 50 yards was slightly above average among the eight bullets tested; the Trophy Bonded Tip traveled perfectly straight through 24.5 inches of gel. The recovered bullet exhibited picture-perfect expansion to well over double the original diameter, with the rear all-copper portion perfectly intact behind the lovely, deadly lead mushroom. It weighed 156.1 grains, which calculates to 87 percent weight retention.
Interestingly, the Trophy Bonded Tip was the only bullet that penetrated less (23.5 inches) at 400 yards than at 50 yards, testifying to its consistent expansion characteristics. Weight retention (175.9 grains) was a remarkable 98 percent, and the expanded bullet measured 0.69 inch, actually larger than at 50 yards.
Granted, the bullet lost more weight at the closer range, which indicates that at some point during its most destructive period in the temporary cavity it was likely rather bigger than the final diameter (which was probably true of most of the bullets tested).
The Trophy Bonded Tip has a relatively high BC of .500, enabling it to maintain downrange velocity and energy well. It's one of those remarkable bullets that you just can't go wrong with, whatever the game. It hits like a runaway freight train and creates a dramatically broad, deep wound. I particularly like it when shooting through massive bone is likely, as when hunting moose or large bears.
One of three boattail, polymer-tipped, bonded bullets included in this test, the Hornady InterBond
is an accurate, aerodynamic projectile that falls right in the middle in regards to retained weight. It exhibits larger expansion than the Nosler AccuBond and Swift Scirocco II and penetrates slightly less than either.
At 50 yards the InterBond expanded immediately and violently, leaving particles of jacket material, lead and even the red polymer tip visible in the massive temporary cavity just inside the gel block. The recovered bullet weighed 140.5 grains (for 78 percent weight retention) after penetrating 23 inches and measured 0.71 inch in diameter — the second-largest expansion of all bullets tested.
Penetration and weight retention (90 percent) at 400 yards were both remarkable, at 24 inches and 163.4 grains. The recovered projectile measured 0.68 inch in diameter.
It seems to me that the InterBond jacket clings to its lead guts a bit better than either the Nosler AccuBond or Swift Scirocco II, resisting the weight loss due to what I think of as the 'smear ' effect. But it also has a slightly thinner jacket at the base, so it retains less of its base in shank-like form.
Since all will perform admirably on heavy game, choosing between the three super-aerodynamic projectiles really comes down to which shoots the best out of your rifle.
Known for superb accuracy and dramatic on-game performance, the Nosler AccuBond
was an early leader in the aerodynamic, bonded, polymer-tipped bullet race, and it's still a leader in many respects. In my tests it lost more weight on impact than the similar Swift and Hornady bullets, but interestingly it also penetrated more than either at 50 yards (25 inches) and scored in the middle at 400 (27 inches). The fragmenting effect on impact makes for dramatic tissue damage, and the fact that fragments strip off reduces final impact diameter (0.60 inch at 50 yards, 0.57 inch at 400), which offers the unexpected benefit of fairly deep penetration.
Weight retention at 50 yards was 118.2 grains, or 66 percent. Even though it had the lowest weight retention, only two other bullets out-penetrated it.
The bullet I shot into gel at 400 yards weighed 133.2 grains for 74 percent retention. Only one other bullet — the Nosler Partition — lost more weight. Penetration was admirable but not remarkable at 27 inches.
Known for effectiveness on game from small whitetails up through caribou, and good results on elk-size game as well, the AccuBond is one of my all-around favorite bullets. With careful shot selection, I wouldn't hesitate to use one on moose or a big bear.
Introduced in 1948, the Nosler Partition
is definitely the veteran premium big game bullet covered here. While not known for offering match-grade accuracy out of every rifle, it shoots surprisingly well out of many. What it's best known for, though, is ultra-effective, reliable performance on game.
I've shot many deer, elk, antelope and coyotes with Partitions in various calibers and weights, and every impact resulted in almost extremely fast kills. The soft nose portion fragments violently, turning impacted vitals into scrambled eggs, while the partitioned-off base turns into a picture-perfect mushroom and pushes on through whatever it encounters — organs, heavy muscle, bone. In a sense, it offers soft-bullet performance on light game and premium-bullet performance on heavy, tough game.
At 50 yards, the bullet I fired into gelatin penetrated 27.5 inches — second only to the Barnes TTSX — and expanded to 0.65 inch, well over double original diameter. Final weight was 124 grains, for 69 percent retention.
Penetration at 400 yards was exactly the same — 27.5 inches — and final diameter was 0.55 inch. Weighing 131.4 grains, the recovered bullet retained 73 percent of its original weight. Temporary cavities at both distances were massive — classic Partition performance on every count.
Heavy-for-caliber Partitions typically offer surprisingly good BCs, enabling them to hold energy well as distances stretch. If your gun shoots them accurately, don't fear using them on just about any North American game in any situation.
Remington Core-Lokt Ultra Bonded
A tougher, bonded version of Remington's much-loved Core-Lokt bullet, the Remington Core-Lokt Ultra Bonded
retains weight better while still expanding violently and dramatically. Flat based and with a 'protected point ' flat nose, it also tends to offer forgiving accuracy out of most rifles, though its BC isn't particularly high.
At 50 yards, the Core-Lokt Ultra Bonded bullet measured an astonishing 0.92 inch — basically triple its original diameter. Even so, penetration was still an admirable 19.5 inches. Retained weight was actually good in light of the massive expansion: 142.6 grains, for 79 percent retention.
Expansion at 400 yards was still colossal — 0.79 inch — and penetration slightly deeper at 22 inches. I was shocked to find that the recovered bullet weighed 173.1 grains, for 96 percent retention. That's well above average in the test.
Of the eight bullets tested, it expanded the most by far and penetrated the least. Both temporary and permanent wound cavities were enormous. Based on those two characteristics, I'd steer hunters toward choosing it for game up to black bears but encourage the use of one of the deeper-penetrating projectiles for use on bigger, tougher game.
Second only to the Barnes TTSX at retaining weight, the Swift A-Frame
hits like a Louisville Slugger, penetrates like a depth charge and kills extraordinarily well. Constructed much like the classic Nosler Partition, it boasts bonding to reduce the risk of core/jacket separation and to enhance retained weight. Though some consider it a bit finicky to coax accuracy out of, and it can't compete with the aerodynamics of the boattailed, polymer-tipped bullets in this test, there are few better smashers when very deep penetration on heavy-boned, big-bodied game is needed.
After shooting into gel at 50 yards, the recovered, expanded A-Frame measured 0.58 inch and weighed 177.3 grains, for 98.5 percent retention. Penetration was an above average 24.5 inches.
Though it had lost more velocity at 400 yards than any of the bullets tested, performance was outstanding. The recovered projectile measured 0.55 inch in diameter and weighed 177.4 grains (almost exactly the same as the 50-yard test), again giving 98.5 percent weight retention. It penetrated 31 inches of gelatin. Fantastic.
That toughness makes the A-Frame a prime choice for the biggest animals in North America, as well as on African plains game, and provides versatility to the hunter who wants to carry one load for everything from small deer, such as Sitka blacktails, up through the bigger bears.
Swift Sciorocco II
Offering higher-than-average BCs, even for boattailed, polymer-tipped bullets, coupled with heavy-jacketed, bonded construction, the Swift Scirocco II
is a superbly tough bullet that performs well on just about any game at any distance. A couple of years ago, I shot a massive black bear at close range and then a 180-class mule deer at long range with this bullet — on the same day. Impact performance in both cases convinced me there are few better bullet choices.
Final expansion diameter at 50 yards was excellent: 0.68 inch. Penetration was slightly below average but still plenty adequate at 24 inches. Weight was 156.1 grains, for 86.7 percent retention — the best of the aerodynamic, bonded, polymer-tipped bullets in the test.
At 400 yards expansion was still almost double-diameter (0.60 inch), and penetration jumped to an above-average 29.5 inches. Only the Barnes TTSX and Swift A-Frame penetrated more. Retained weight was 167.1 grains, for 93 percent — again the best of its ilk.
Choose this bullet any time you want fantastic performance on distant game coupled with toughness capable of handling close-range impacts on heavy bones and dense muscle.
When I started this test, I expected more dispersion in performance characteristics among the bullets, which just demonstrates how good today's crop of premium bullets really is. Any one of them will give yeoman's service.
That said, there are a few standouts. For pentrations, I'd look hard at the Barnes TTSX, Swift A-Frame and Nosler Partition. When a massive energy dump and slightly less penetration is desired, Remington's Core-Lokt Ultra Bonded is a clear standout. If you're looking for aerodynamics and downrange performance, any of the boattail, polymer-tipped, bonded bullets will work great. And though all the bullets tested here are good, versatile performers, Federal's Trophy Bonded Tip is possibly the best for across-the-board performance.