The Case For Copper

Copper bullets are gaining ground with big-game hunters, and for good reason. They hold together, penetrate deep through heavy bone and muscle, and leave no lead behind in your meat. For Alaska hunters chasing moose, caribou, and bears, they just might be the best choice available.

Story by George Krumm. Originally published in the Summer 2024 issue.

In 1976, I shot my first big-game animal. It was a spike blacktail buck, and the range was about 25 feet, maybe less. I hunted with a Remington 760 pump-action rifle in .270 Winchester back then, using 130-grain Remington Core-Lokt pointed soft point ammunition. The shot was behind the shoulder, and it passed through both lungs before exiting. At roughly 3,000 fps, that bullet probably fragmented in an extreme way, but most of it blew out the other side of the deer. The little buck didn’t fall down dead; instead, it fell down, then immediately got up, ran downhill right past me, and piled up about 20 yards down the hill. There was a tremendous exit wound, and heavy bloodshot tissue on both sides of the animal.

Remington has been making Core-Lokt ammo for more than 75 years. Cup-and-core bullets like this have been the mainstay of hunters for a very long time. However, monolithic bullets are making a strong showing in ammo sales these days. What’s more, for Alaska hunters, monolithic bullets just might be the best choice.

Like all the different bullet designs, monolithic bullets (sometimes called copper bullets, though that might be a little imprecise), have strengths and weaknesses. For my own Alaska hunting, I’ll use monolithic bullets, as long as I’ve found some that shoot well in whatever rifle I’m carrying. Read on and you’ll learn why.

Before I make the case for copper bullets (monolithic), it’s important to understand the strengths and weaknesses of other bullet types commonly used for big-game rifle hunting in Alaska.

Cup-and-Core

Cup-and-core bullets are probably the most used big-game rifle bullets in North America. This style of bullet has been around for well over 100 years. Typical construction is a copper jacket with a lead core. They are held together simply by the mechanical squeezing of the copper jacket around the lead core. Sometimes there are notches inside the jacket to help grip the lead. These bullets have killed everything on the North American continent, so they’re proven effective in most situations. They tend to be very accurate, inexpensive compared to some of the other bullet types, and they reliably expand, in some cases down to 1,600 fps. They aren’t perfect, though.

Fragmentation at High Velocities

At high velocities, either from close range, magnum cartridges, or both, these bullets can fragment excessively, limiting penetration, and ruining a lot of meat. Sometimes these fragments wind up in the meat. Sometimes they wind up in the offal, presenting a danger to birds and scavengers that feed on the gut pile and carcass. Additionally, because they tend to fragment, and sometimes the jacket actually separates from the core, fragments of lead can travel well outside the primary wound channel. On a heavily muscled, heavy-boned animal like a moose, fragmentation could result in insufficient penetration to reach the vitals, meaning a suffering animal. Such fragmentation on a brown bear could be dangerous for you if the bear is close. It goes without saying that shot placement is always important. Cup-and-core bullets might not be a good choice for large game animals like an elk, a moose, or a bear that is quartering toward you.

Partitioned

The original partitioned bullet was the Nosler Partition. This bullet design still features a copper jacket, but the lead core is divided in two, separated by a copper partition. This allows the front of the jacket and lead core to expand much like a cup-and-core bullet, but the rear lead core is encased in jacket material, so it stays together and continues to penetrate. Partitioned bullets generally stay together and penetrate well, even after impacting tough muscle and bone. Partitioned bullets are well respected throughout the world because of their reliable, consistent terminal performance.

Downsides of Partitioned Bullets

There are a few downsides to partitioned bullets. First, they are very expensive, either as bullets to load yourself or as factory ammo. Second, they have little boattail, so they have a rather low ballistic coefficient (BC) compared to many more modern bullets. This makes them not the best choice for shooting beyond traditional ranges, but in Alaska, the average shot at big-game is certainly less than 250 yards, so super-high ballistic-coefficient bullets are not needed for your average shot. However, if you think you might need to shoot past 400 yards someday (assuming you have practiced and have the skill to do so), then partitioned bullets might not be the best choice. Third, the front half can still fragment or separate from the shank of the bullet and distribute lead fragments in the meat or carcass.

Bonded

Bonded bullets came about to make a bullet that would stay together without the expense of building a partition into the bullet. Essentially, the lead core and copper jacket are welded together, rather than just squeezed together mechanically like cup-and-core bullets. Bonded bullets typically have a softer, thicker pure-copper jacket than cup-and-core bullets, and soft, pure-lead core. The result is a bullet with partition-like integrity. Since the jacket and core are softer materials than cup-and-core bullets, they will expand at lower velocities than cup-and-core bullets—down to 1,500 fps or so. What’s more, many of them have sleek shapes with long ogives and boattails, a high BC as a result, and they’re suitable for use from close to far. Examples of cartridges made with bonded bullets with higher BCs include the Federal Terminal Ascent and Nosler AccuBond Long Range (ABLR). Both are rather spendy, though. At $80 a box for .300 Win Mag Terminal Ascent, that’s $4 a pop. The Noslers are even more expensive: $120 a box for .300 Win Mag; that’s $6 every time you pull the trigger…

Monolithic (“copper”)

Monolithic big-game bullets are bullets that are made of a single type of metal. Most commonly, they’re made of copper or a copper alloy, have some sort of hollow point, and often have a polymer tip to boost BC and help initiate expansion.

The first commercially available monolithic big-game bullet was the Barnes X, which came out in 1989. These immediately became known for one of the key advantages to monolithic copper or copper-alloy bullets: reliable, extremely good penetration and bullet integrity. The original Barnes X bullet wasn’t without issues, though. Chief among them were more bore fouling; increased pressure; and lower BC than many cup-and-core bullets and therefore more wind drift, more bullet drop, and less accuracy. Barnes monolithic bullets evolved over time with the Triple Shock bullet (TSX) coming out in 2003. The TSX reduced the fouling and pressure issue because it had four cannelures, which give the copper being scraped off by the rifling a place to go. Cannelures are found on most monolithic big-game bullets today. The Tipped Triple Shock (TTSX) came out in 2008 and had a polymer tip and a boattail; and the LRX (Long Range) in 2011 which had all the features of the TTSX, but a better ogive, and longer boattail. Many bullet makers came out with their own monolithic projectiles after the original Barnes X bullet.

Advantages of Monolithic Bullets

There are many advantages to using monolithic big-game bullets. First, and perhaps most valuable, is that you get better penetration than all the other bullet types for similar-sized projectiles. They can encounter heavy bone and muscle and will likely drive on through and usually exit, leaving a good blood trail.

Next, bullet weight retention is astonishingly good even at really close ranges. Most monolithic bullets will retain 95% or more of their original weight; this is part of the reason they penetrate so well. Monolithic bullets exhibit the highest bullet integrity of all the big-game bullet types. These bullets stay intact—they almost never fragment. Because they stay intact, meat damage is minimal compared to other bullet types. Because weight retention is so high, you could downsize your bullet a little and still have outstanding penetration, plus higher velocity and less recoil.

Monolithic bullets are environmentally friendly. They’re non-toxic, and there is no concern with eagles or other scavengers working over a carcass and getting lead poisoning from fragmented lead-core bullets. Along the same lines, with monolithic projectiles, you don’t have to worry about lead being in the meat you take home.

Non-lead projectiles are currently required in California. It is likely that at some point in the future, other states will follow suit.

Generally, good quality factory ammo with monolithic bullets can be had for reasonable prices. For example: Winchester Copper Impact, 180-grain .300 Win Mag, is $40 to $50 for a box of 20. Hornady Outfitter 180-grain .300 Win Mag, is $45 for a box of 20.

Disadvantages of Monolithic Bullets

Like all the other bullet types, monolithic big-game bullets have some disadvantages. They are very long for their weight, and this can limit bullet weight choice due to seating depth in the case, and cartridge overall length. They also tend to have lower BCs than lead-core bullets, leading to more wind drift, and faster bullet drop. To compensate for this, shooting a light monolithic bullet will result in more velocity, which can help with wind drift and bullet drop. In many cases, you will have to shoot a lighter monolithic bullet simply because they are longer for a given weight than lead-core bullets.

Some rifles don’t shoot monolithic bullets very well. You may have to try a few different types of factory ammo, or load a few different loads if you’re reloading, to find one that your rifle likes. Of course, this is true with the other bullet types, too.

Velocity and Expansion in Magnum Cartridges

Monolithic projectiles have a need for speed. That is, to reliably expand, they need to travel fast. Some sources say 1,800 fps is fast enough for good expansion. I like the more conservative 2,000 fps. Because of this, monolithic bullets work well in magnum calibers. If a monolithic bullet is going too slow, it will pencil through the animal and not cause much hydrostatic shock, and maybe not a lot of bleeding. You must be aware of how fast your bullet is going at different ranges to ensure expansion. Below are some examples of different calibers and monolithic-projectile expansion capabilities.

In 6.5 PRC (Precision Rifle Cartridge), Hornady’s Outfitter line of ammo uses their 130-grain CX (copper alloy expanding) bullet. The bullet leaves the rifle at roughly 3,000 fps, and at 500 yards, is still traveling 2,086 fps. So, it’s reasonable to predict that ammo and bullet will be effective all the way out to 500 yards.

Outfitter ammo in 7 PRC uses a 160-grain CX bullet traveling at 3,000 fps at the muzzle. At 500 yards, that bullet is still zipping along at 2,254 fps. It’s reasonable to expect excellent performance with this ammo and bullet out to 500 yards.

Outfitter ammo in .300 Win Mag uses a 180-grain CX bullet that leaves the muzzle at 2,960 fps. At 500 yards, the bullet is still traveling at 2,040 fps. Like with the two PRC ammos above, you can expect adequate expansion with this ammo/bullet all the way out to 500 yards.

Winchester Copper Impact ammo in .300 Win Mag uses a 180-grain bullet that performs almost identically to the Hornady Outfitter ammo as far as velocity is concerned. It leaves the muzzle at 2,950 fps, and at 500 yards is still traveling at 2,031 fps. This ammo is effective out to 500 yards, too.

Interestingly, I’ve shot both the Hornady Outfitter ammo and the Winchester Copper Impact in my Savage 110 Storm .300 Win Mag. Both shot a little less than one MOA, five-shot groups in that rifle.

How Standard Cartridges Compare

It’s important to note that not all calibers will maintain velocity, and thus expansion capability, as far as the magnums mentioned above will. For example, the venerable .30-06 in Hornady Outfitter ammo uses a 180-grain CX bullet that leaves the muzzle at 2,700 fps. At 300 yards, the velocity has dropped to 2,156 fps. At 400 yards, 1,989 fps. Since I like to see 2,000 fps of velocity for good expansion with a monolithic bullet, I consider this ammo good out to about 380 yards.

.30-06 Hornady Outfitter ammo is also available with a 150-grain CX bullet. This bullet leaves the muzzle at 3,000 fps. At 400 yards, it’s still going 2,158 fps. At 500, it drops to 1,972, so by my way of thinking, the 150-grain ’06 ammo is good out to about 480 yards—about 100 yards farther than the 180-grain Outfitter .30-06 ammo. Naturally, the lighter bullet will have less recoil, too.

In Alaska, based on an informal poll I’ve done, the average shot taken at big-game is less than 250 yards. Every single monolithic load mentioned above is effective well beyond that range.

If you want to reload using monolithic bullets, you have lots of choices, and you may be able to develop a load that shoots exceptionally well in your rifle. Something to keep in mind is that since monolithic bullets are generally longer than lead-core bullets, you will have to abide by the recommended twist rate on the box of bullets you plan to load.

Why Monolithic Bullets Make Sense in Alaska

Monolithic big-game bullets are here to stay. What’s more, it is possible that more states will follow California and require non-lead bullets for big-game hunting. But even if they don’t, assuming you find a monolithic load that shoots acceptably well in your rifle, and if you hunt at ranges where your bullet will still be traveling at 2,000 fps or more, a monolithic bullet will provide good expansion and amazing penetration even through heavy bone and muscle, pretty much regardless of the shot angle. An added consideration for Alaska hunters is that we are often hunting in areas where the presence of dangerous game (brown bears/grizzly bears) is real. There is something to be said about knowing a monolithic bullet will stay together and provide maximum penetration on large game at ranges from point-blank to distances well beyond where most Alaska game is taken.

George Krumm is the Editor of both Fish Alaska and Hunt Alaska magazines. He is also a freelance writer/photographer. George has fished and hunted from Patagonia to Alaska and has been writing professionally since 2003. George writes several feature articles per year for various publications, plus he writes the “Editor’s Creel” and “Flyfishing” columns for Fish Alaska magazine, and he wrote the “Stillwater” (flyfishing) column in Fish Alaska for more than nine years. George lived in Alaska for 20 years and now makes his home in the Pacific Northwest.

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