Bonded Core Beauties, Not Your Grandad’s Bullets

Ready for duty, .300 Win. Mag. cartridges loaded with Swift's bonded core Scirocco II bullets.
Ready for duty, .300 Win. Mag. cartridges loaded with Swift's bonded core Scirocco II bullets. Photo courtesy Massaro Media Group and JNJphotographics.

In the fall of ’46, when Mr. John Nosler raised his .300 Holland & Holland Magnum and held true on the vitals of that famous moose that refused to die, the premium bullet industry was about to be born.

The failure of the traditional cup-and-core bullets led to the development of the first (and still viable!) premium offering: the Nosler Partition. Hunters around the world have relied on its combination of expansion and penetration for generations, and that single development caused the engineers of the bullet world to rethink bullet design.

A traditional bullet is made of a lead core, swaged into a copper cup jacket. At moderate velocities, these bullets have performed just fine on game that is appropriate for the bullet size and weight. However, when the animals get large, and the hide and bone becomes thick and difficult to penetrate, the shortcomings of the traditional bullet design come to the forefront.

Moose, large bears, bison, elk, Cape buffalo and the like all make a good case for more than a standard bullet. For years, professional hunters in Africa recommended solid (non-expanding) bullets on the heavyweights, because of the unreliable penetration associated with a conventional softpoint, even in the big calibers.

Well, modern technology has delivered the solution to the softpoint problem: the bonded core bullet. The lead core is chemically bonded to the copper jacket, to allow for good expansion (like a softpoint) and making the bullet tough enough to ensure deep penetration (like a solid).

The common problem of jacket separation, often associated with boat tail cup-and-core bullets has been resolved, giving us shooters the high ballistic coefficient we love for long range shooting, with excellent terminal performance once the game is hit.

Nosler has its Accubond, with a polymer tip and boat tail. There are others similarly constructed; the Hornady InterBond, and the Swift Scirocco II. These make great all-around bullets for the hunter, as they can be very accurate and perform well at standard velocities yet can be driven to the high speeds of the largest magnum without fear of bullet failure.

Mr. Nosler’s design incorporated a dual core, one front and one back, separated by the “Partition”. Bill Hober at Swift beefed the idea up by bonding the core, and his Swift A-Frame is, in my opinion, one of the best big game bullets ever produced. I’ve personally taken eleven different species of African game with it (in various calibers) and numerous heads of North American game. Weight retention often exceeds 90%, and I’ve seen it penetrate the tough shoulder bones of Cape buffalo and eland, and be recovered just under the offside skin. You really can’t argue with that kind of performance.

Classic expansion of a bonded core bullet, a 400-grain .416 Swift A-Frame recovered from a Cape Buffalo.
Classic expansion of a bonded core bullet, a 400-grain .416 Swift A-Frame recovered from a Cape Buffalo. Photo courtesy Massaro Media Group and JNJphotographics.

The Trophy Bonded Bear Claw is a similar design, but only uses a lead core in the front, leaving a solid copper shank in the rear. It performs similarly to the A-Frame. The Australian firm of Woodleigh makes a bonded core called the Weldcore, a great bullet that is made to the same nose profile and shape as the old Kynoch ammunition, so it will perform well in the older double rifles and bolt guns still in service. Weldcores have a great reputation, and deservedly so; their performance engenders an awful lot of confidence in those hunters who pursue dangerous game.

North Fork Bullets have a bonded core bullet also, their softpoint semi-spitzer. It is a pure lead core bonded to a pure copper jacket, with grooves machined into the rear portion of the bullet to keep pressures low. It does just that, and makes an accurate, hard hitting hunting bullet. I have great expectations for this bullet, and plan to take it in the field this fall.

The nice thing about these bullets is that they require no special loading techniques, and often your favorite cup-and-core load will prove accurate with the bonded core bullets.

So, if you’re hunting large mammals, or if you’re headed off on the hunt of a lifetime, you can hedge your bets by loading up some bonded core ammunition. Remember, the bullet, and only the bullet, is the only portion of the rifle/optics/ammunition that ever touches the game animal, so be sure to use the best you can get.

44-Targetposters-pack-GD-reduced-300NEXT STEP: Download Your Free Storm Tactical Printable Target Pack

62 Printable MOA Targets with DOT Drills - Rifle Range in YARDS This impressive target pack from our friends at Storm Tactical contains 62 printable targets for rifle and handgun range use. Target grids and bullseye sizes are in MOA. Ideal for long-range shooting!

Subscribe to the Gun Digest email newsletter and we'll send your print-at-home target pack right away. Just enter your email address below.


Please enter your comment!
Please enter your name here

This site uses Akismet to reduce spam. Learn how your comment data is processed.