Rifle Bullets Basics

Between all the marketing hype and various experts offering differing opinions, it’s easy to become confused when selecting a hunting bullet.

I’ve spent most of my adult life studying bullets by shooting them into animals and various ballistic test mediums, and I’ve learned a thing or two by getting my hands dirty. Hunters like to look at recovered bullets and make assumptions about how well they kill. This is near impossible. The best evidence is the damage you find inside the animal, how the animal reacts when shot and, alternatively, by testing in ordnance gelatin.

Bullet Classifications
Hunting bullets can be placed into three classifications: fragmenting, expanding and penetrating.

Fragmenting bullets are mostly varmint bullets that come apart, shedding the majority of their weight.

Penetrating bullets retain most of their weight and hardly deform at all. Penetrators are best suited to dangerous game hunting.

The retained weight of the bullet is not as important as bullet construction. This 85-grain Nosler Partition put down a 500-plus-pound wildebeest at 180 yards.

Between these extremes you’ll find the bulk of the big game bullets. This expanding category is where we see wide variations in bullet behavior and we can subdivide it into maximum expanding, minimum expanding and balanced bullets. Minimum expanding bullets penetrate better than they damage tissue, maximum expanding bullets do just the opposite, and balanced bullets deliver a balanced approach to expansion and penetration.

Bullet Construction
Similarly, bullets are built in three basic ways.

  • Cup-and-core bullets, like the Remington Core-Lokt, are considered the standard design; they’re assembled by placing a lead or alloy core inside a copper or gilding metal jacket.
  • Bonded bullets, such as the Nosler AccuBond, are similar but the core is fused to the jacket.
  • Mono-metal bullets are the newest fad. They’re extruded or machined from a single slug of copper or gilding metal. The Barnes Triple Shock and Hornady GMX are mono-metal bullets.

Where it gets complicated is discerning what each type will do when it hits an animal. Mono-metal bullets are the most balanced; they generally expand to about twice their original diameter and retain most of their weight. This allows them to penetrate deep.

When a small caliber, high-velocity cartridge, like the .223 Rem., is used for big game, consider a bonded or mono-metal bullet. It will help with penetration.

But, for best results, mono-metal bullets need velocity. Most will only show minimal expansion if they impact at speeds slower than 2,000 fps. On the plus side, mono-metal bullets can handle high speed impacts well over 3,000 fps and still hold together.

Most cup-and-core bullets perform as maximum expanding bullets and damage lots of tissue with the wide wound cavity they create. Bonded bullets are similar to cup-and-core bullets, but most will deliver less than ideal expansion if they impact at speeds slower than about 1,800 fps. Like mono-metal bullets, bonded bullets need velocity—and they can handle it. Cup and core bullets, on the other hand, can break apart when impacting heavy bone or at very high speeds.

Impact velocity matters to the bullet. These Swift Scirocco bullets impacted at vastly different speeds. The one on the left that impacted at more than 3,000 fps would classify as a maximum expanding bullet. The one on the right, which impacted at less than 2,000 fps, would be a minimum-expanding bullet.

Bullets that fall within the minimum expanding category are not engineered to perform that way. Most often, a minimum- expanding bullet is a maximum expanding or balanced bullet that has slowed to a speed below what is necessary for full expansion. In other words, the bullet has traveled so far down range that its velocity has dropped to a point where it cannot fully expand. Partial velocity loss can even make a maximum expanding bullet act like a balanced bullet.

A Major Misconception
As interesting as all this might be, bullet selection is still complicated. This is partly because of misconceptions on the part of hunters and marketing hype on the part of manufactures.

Berger VLD Hunting bullets are a maximum expanding type of bullet that will damage vast amounts of tissue and put animals down fast. However, they will not penetrate tremendously deep. They are a good choice for long-range hunting because they will expand at low velocities.

One of the biggest misconceptions is the importance of bullet weight and retained weight. and how they impact a bullet’s ability to kill. Bullets kill by generating blood loss—not by being heavy or retaining their weight. Weight can help with penetration, but unless you’re using small caliber lightweight bullets to start with, penetration is generally not an issue.

Bullet Selection Guidelines
So, how do you choose? Fortunately, shot placement usually matters more than the bullet you select. All modern hunting projectiles work, some will penetrate deeper and some will put animals down faster.

    Here are some generalized suggestions you might consider.
  • Select a mid-range bullet weight to obtain the best ballistic balance. For example, in the .308 Win., the 165-grain weight will deliver an optimum equilibrium of energy on target, trajectory and down-range velocity.
  • For high-impact velocities or for rifles with muzzle velocities faster than 3,000 fps, consider mono-metal or bonded bullets. This will circumvent the worry of bullet blow up at high impact speeds. These are also good bullets for use with high velocity, small caliber cartridges such as the .223 Rem. or the .243 Win., especially when used on game larger than deer.
  • Most common big game cartridges, with muzzle velocities below 3,000 fps, standard cup-and-core bullets work exceptionally well. They expand wide, provide adequate penetration and put animals down fast. When tackling bigger-boned game, consider a bonded or mono-metal bullet to prevent bullet jacket and core separation, in case large bones are hit.
  • Avoid mono-metal and bonded bullets for extreme long range where impact velocities are less than 1,800 fps. These bullets need velocity to do their best work.

  • Bullet construction, in conjunction with impact velocity, determines terminal performance. All of these .308 caliber, 150-grain bullets impacted at the same speed ... but as you can see they deformed very differently. (Left to right: Barnes Triple Shock, Nosler Ballistic Tip, Nosler AccuBond, Hornady InterBond.)

    In the end there, is no magic bullet—there are only good bullets that deliver different types of terminal performance. The deeper a bullet penetrates, the smaller the wound cavity will be. And, given the common broadside, vital organ shot, the longer the animal will likely remain on its feet. Larger wound cavities come with reduced penetration but tend to cause more blood loss and drop animals faster.

    Regardless of the caliber or weight, Barnes Triple Shock bullets perform very consistently. They usually expand to twice their original diameter and retain all their weight. However, even though they penetrate deeply, the wound cavity they create is small compared to those created by cup-and-core style bullets.

    The right answer will depend on the animal, the cartridge, the distance to the target and, most importantly, on shot placement.

    Hunters who know how to shoot have a way of making almost any bullet look good.

    Bullet Examples By Design
    Cup-And-Core: Berger VLD, Hornady InterLock, Hornady SST, Nosler Ballistic Tip, Remington AccuTip, Remington Core- Lokt, Sierra Pro Hunter, Winchester Power Point

    Bonded: Federal Fusion, Hornady InterBond, Nosler AccuBond, Nosler Partition (Non-Bonded with Bonded Performance), Swift Scirocco, Swift A-Frame (Non-Bonded with Bonded Performance)

    Mono-Metal: Barnes Triple Shock (Tipped Triple Shock), Federal Trophy Copper, Hornady GMX, Nosler E-Tip, Winchester Razorback

    Want to read most about ballistics? Check out this Dummies Guide to Ballistics at Empty Cases.

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