The Case for Copper Bullets

This is a guest post by Andrew Betts

Copper Bullets

The very first firearms literally fired rocks. Not long after that, iron and lead projectiles came into use. Lead has the advantage of being plentiful (and therefore inexpensive) as well as being very dense and soft. The density allows a bullet to carry velocity downrange better and the softness allows a ball or bullet to obdurate (“smoosh” into and form against) to the rifling in a barrel. Lead has limits to what it can do when it reaches the target, though. At high velocity it can fragment, which reduces the bullet’s weight and prevents it from driving as deeply into tissue. About 25 years ago, Barnes introduced the X-Bullet, which was an all copper hollow point. Since then they have continued to improve their line of all copper bullets and other companies have produced similar offerings.

The original interest in solid copper bullets was their performance for hunting but they have recently gained some favor for use in defensive ammunition.

One of the features that makes a solid copper bullet especially attractive for defense is that they have the ability to expand to a very large diameter and do so consistently despite being fired through a variety of intermediate materials, especially heavy clothing. The ability of a solid copper bullet such as the TAC-XP to expand despite heavy clothing and at relatively low velocity is hard to match in a more traditional lead core bullet.

While the performance in the above test may not be revolutionary, it is precisely what we wish to see from a defensive pistol bullet. 0.625” average expanded diameter with just over 14.2” of penetration is quite simply textbook perfect performance.

Solid copper handgun bullets also perform well at high velocity, though. In the test below, we can see that the 125 gr DPX performed perfectly at the 1,300 fps typical of a 4” .357 magnum, but perhaps more telling is the fact that it even performed fairly well when fired from a 16” carbine. The extra 300 fps would likely have been just too much for any lead core hollow point to hold together but the solid copper bullet stayed relatively intact.

 

This sort of performance is not limited to handgun cartridges, either. The Barnes TSX is able to expand over a wide range of velocities as well and can penetrate deeply. That matters a lot for a fighting rifle. The ability to perform as well, or nearly as well, at 300 yards as at 5 yards is a desirable trait. It is also “barrier blind”, which means it is able to do these things even after passing through intermediate barriers like plywood, auto glass, and sheet metal.

Recently, it has become available with a diameter of 0.310”, which means that AK shooters and others who prefer the 7.62x39mm cartridge can enjoy the significant benefits of this bullet. Not too long ago, the .223/5.56mm and .308 Win almost exclusively reaped the benefits of new bullet technology. In recent years, though, some of these bullet designs have started to become available to the 7.62x39mm.

Not all solid copper bullets are great performers, though. Some are simply not well designed and/or suited to the cartridge they are paired with such as this 10mm 155 gr COP (copper only projectile).

It looks very much like other solid copper hollow points such as the Barnes TAC-XP and the Corbon DPX, but it penetrated only about 10 inches, even at the relatively sedate velocity of 1,008 fps. It may have penetrated more deeply if driven to higher velocity, though. Lead core bullets usually penetrate less as velocity increases, after the threshold at which expansion begins, but solid copper bullets do seem to penetrate more deeply with higher velocity. Still, properly designed copper bullets can perform well across a significant velocity range so this bullet would be well served by a redesign and a little less aggressive expansion.

In recent years, it seems that every other month another manufacturer produces some sort of newfangled wonder bullet and they seem to always be made of solid copper. Some offer performance that is not categorically terrible, such as the Lehigh Controlled Fracturing Bullet.

The base of the bullet certainly penetrates deeply enough but it is only a small piece. The petals do create a relatively large area of disruption but they do not penetrate very deeply. It is difficult to apply the usual standards to this projectile, but it just does not add up. At least it makes the minimum penetration requirements, though.

There are other solid copper bullets that are quite simply garbage. They are not simply atypical; they just perform terribly, usually due to rapid fragmentation and inadequate penetration. An example of this type is the Liberty Civil Defense 10mm 60 gr Fragmenting Monolithic Copper Hollow Point.

Despite its impressive sounding name and rifle-like velocity over 2,300 fps, the low mass and low sectional density  produced predictably poor penetration of only 7 ½ inches, which is completely inadequate for defense.

Whether you are attracted to copper ammunition because of the impressive capabilities of bullets like the TSX, TAC-XP, and DPX, or you are required to use copper bullets because of state restrictions on lead projectiles, there are some excellent choices available. Avoid anything that sounds too good to be true and stick with the well proven and vetted companies.

 

Andrew Betts served with the Arizona National Guard for over 12 years, including a tour to Afghanistan. Visit his YouTube Channel for more great shooting information.