Match Hollowpoints – Interior, Exterior, and Terminal Ballistics

My wife reads a lot of “who dunnit” mystery novels.  The one she’s reading now addresses long-range marksmanship and the use of hollowpoint “match” bullets.  As a person normally 100% uninterested guns and shooting, she had a very good question for me; “Why do they use hollowpoints for accuracy”?  This lead to a very interesting discussion– one uninterested in guns was trying to understand something that few gun enthusiasts understand completely and rarely discuss in such detail.

I had to admit I was at something of a loss.  My best understanding is that the hollowpoint bullet jacket can be manufactured to higher standards of concentricity (the mass being better centered around the mechanical center so as to avoid wobble in flight) and consistency of mass and shape.  That is all true, but exactly why it is true I was at a loss to explain with certainty.  My best guesses are that it has to do with the process of forming the jacket’s shape, and with the insertion of the bullet’s lead core, but I don’t know the actual processes used in bullet manufacturing.

I also told her it was my opinion that since the hollowpoint jacket (having a closed copper base due to the way it’s constructed) allows none of the bullet’s lead base to melt away during the intense heat of firing, it is going to retain its mass, and therefore its consistency of mass from shot to shot, better than the open base of a standard full metal jacket bullet.  I’ve also read that the open-base FMJ can allow the jacket to partially separate from the core at the base under the pressure of firing.  If so, that would certainly alter its flight slightly and at random.

She explained that it was her understanding that hollowpoints were used to cause more trauma inside the target, and I told her that she was correct.  She was having a hard time understanding that there is no direct correlation between the objectives behind hollowpoint “match” bullet designs, and the hollowpoint bullets designed to expand and cause more damage.  This was getting too technical for a layperson, but her interest was piqued by the story she was reading.  I had to explain that hollowpoints designed specifically for expansion on impact have a wide range of designs, operating velocities and applications, and that match hollowpoints have nothing to do with any of that.  The match bullets are only designed for accuracy, with no regard to their effects on a target.

That being the case, one can nonetheless do a little experimentation.  Manufacturers of match rifle bullets usually make a point of telling the customer that they are NOT intended, and should not be used for, hunting.  There is one company, Burger Bullets, that touts their match VLD (Very Low Drag) hollowpoints as hunting bullets.  I’ve been loading Berger 7 mm bullets in 280 Remington for my son’s use at Boomershoot, and since he keeps his rifle zeroed for that load, he has also used the VLDs for hunting.  This particular bullet has a light (read weak) jacket, and while it is an awesome animal stopper, it explodes at high velocity inside the animal due to its light construction and causes major damage to any meat it comes near.  It also tears a large hole in the hide for those of us who keep the skins.  They make a tiny entry wound and a softball-sized exit wound.  That would be OK if the shot placement and angle were ideal because only the heart/lung cavity would be so effected (then too, we like to eat the heart if it’s intact).  Other match hollowpoints have heavier jackets that don’t behave much different, on impact, from a standard FMJ bullet.

Practicing for Boomershoot last week, we found one of our 30 caliber match bullet jackets behind a 2′ diameter rotten, wet log that it had penetrated.  Just the jacket, turned nearly inside-out, with no lead core.  The hollowpoint tip was almost perfectly intact, and so behaved radically different from a hollowpoint hunting or defense bullet.  The bullet had traveled 400 yards, entered and then yawed violently sideways inside the log.  The intense pressure of deceleration caused the heavier lead core to burst out the side of the jacket, separating completely.  The open-sided jacket followed through to drop on the ground just behind the log.  These match bullets were loaded in .308 Winchester cartridges made by Black Hills Ammunition.  We were using 168 and 175 grain, “red box” new loads.  I think the bullets they use in these loads are from Sierra, but don’t quote me on that.  You can call them and ask if you’re curious.

11 thoughts on “Match Hollowpoints – Interior, Exterior, and Terminal Ballistics

  1. My understanding is that the reason for the hollowpoint (or ‘open tip’ if you fly that way) is that it moves the center of gravity rearward and thus enhances stable long range flight.

  2. It does move the center of gravity slightly rearward but that makes it less stable.

    Think of dart, which is obviously extremely stable, which has it center of gravity far forward of its geometric center. Or try throwing a sock with an orange in the toe. Which end goes first to make it the most stable?

    I think Lyle is much closer to the correct answer and Wikipedia is full of it on this topic.

    I can’t find it on the Sierra web site, but I’m pretty sure Sierra claims the hollow point for their Match King bullets is simply a manufacturing artifact. The base of the bullet is a critical factor in bullet accuracy. They can make a more uniform base with a closed base than with an open base. They would have both a closed tip and closed base if they could but they use the hollow point in the manufacturing process. They insert a punch into the hollow point to push the completed bullet out of a die.

  3. It’s all about stability. What a hollowpoint does in the case of match ammunition is move the Center of Pressure (the point where the air resistance acts) rearward; the CoP acts at the bottom of the cavity. The idea is to move the CoP rearward of the Center of Gravity. This is why darts or the orange in a sock example fly heavy end first: mass is concentrated at one end (CG very far forward), and the drag force at the other (CoP very far to the rear). If the CoP is forward of the CG, you end up with an inverted pendulum configuration, and the bullet will tend to tumble in flight. If the CoP is rearward of the CG, it has a stabilizing effect, in the same way that a pendulum will eventually return to a vertical position after being disturbed.

  4. There’s also an aerodynamic factor. The air captured in the cavity is going to create a perfectly regular barrier (like a meniscus on a liquid — which, under these conditions, air is) at the point that would be very difficult to duplicate with any solid material. That’s going to give less irregular drag at the tip to pull the bullet out of its course.

  5. Lots of good supposition here, but the facts are different than what the supposition is. This is direct from Berger Bullets:

    Just a slight correction here; the hollow points are simply the unavoidable result of the manufacturing process. If the nose could be (economically) closed completely, that’s what they’d be doing. As it is, there has been several aftermarket attempts by folks like Col. Marty Fackler, MD, and even Lake City to close those tips, which actually does (ever so slightly) improve ballistics. In short, even though they are “open tip” bullets, they behave like FMJs in tissue. This is why these bullets are legal under the laws of land warfare, and have been certified as such by our own JAG. With those minor corrections, your comments were dead on; they aren’t designed to mushroom.

    Berger has their line of .338″ bullets coming out in the next few months. Made with thinner jackets than the SMK, I’ll bet they’d answer most of the problem seen here, with superb accuracy to boot.

    Kevin Thomas
    Berger Bullets

  6. Bill is of course correct; you either have an open base or an open tip. There are electro-plated bullets that have no opening, but apparently they aren’t in the running as no one currently makes a plated match bullet for high power cartridges.

    As an aside, I have written about open-base FMJ bullets fouling a .30 carbine’s gas chamber with a hard lead residue, and the same thing happens with an AR– some of the lead “aerosol” that melts away from the base ends up as a hard dross build-up behind the bolt inside the AR bolt carrier. Using open tip/solid base bullets prevents this type of fouling. I don’t know their specific reasoning for it, but some surplus 30 cal AP rounds have what appears to be a separate copper gas check at the base of the FMJ bullet. I would expect those to fire more cleanly, as they would behave more like a solid-base bullet inside the barrel.

  7. As far as the Berger VLDs being good for hunting… what I read a little while back was that it was completely unintentional. Some people had used them and had been reporting really good results. In their own testing to see what was going on that was making these target bullets so good for hunting, they found that they expand well, and they tend to go much farther into the animal before expanding than regular hunting bullets do.

    The end result is that they usually get into the vitals before they expand instead of wasting all that expanding goodness on muscle tissue and therefore not getting as much penetration nor doing as much damage to the organs.

  8. GunGeek; I don’t know whether “expand” or “detonate” is the correct word to describe what happens to a VLD in tissue. We have yet to recover any fragments larger than a grain of sand. It could be that some of the bullet holds together and passes on through– I just don’t know. In the same 280 caliber a standard softpoint hunting bullet, designed to expand and hold together, makes a smaller exit hole than the VLD. As for penetration; Son has shot several white-tailed deer, at different angles, with the 7 mm VLD, and every bullet has simply exploded out the far side, in one case pulverizing a scapula on the way out. (gee, we’re getting pretty graphic here now, aren’t we?) Penetrations isn’t going to be an issue unless we’re talking some far larger game.

  9. Ref moving the center of balance back, my understanding is that this is what the British did to increase the lethality of their MkVII ball in .303. They tried putting an aluminum insert in the nose of the jacket with the lead core behind; very stable and accurate in flight, and when it hit a soft target it went unstable more quickly than standard ball. I think Box o’ Truth tried some of these, and some made during WWII that had a wood insert; the latter went dramatically unstable after impact.

    A while back I tried loading some Sierra 110-grain Varminter HP bullets for .30 Carbine. Quite accurate, so I tried them on milk jugs. At 50 yards, the bullet would penetrate four jugs- 24″ of water- and be found in the bottom of the fifth jug. They were bent like a banana, split open on the inside of the curve with the core barely hanging in; the nose was undeformed with all the bullet damage behind it. Looks like the large empty cavity in front of the jacket, at the 1930fps the load gave, caused the bullet to act like the MkVII ball.

  10. “So what was the mystery novel?”

    One Shot by Lee Child. This one has already been put away. She burns through paperback novels at a rate of several per week, typically never commenting on them. Since this one had shooting as something of a central theme, she consulted her “resident expert”, such as he is, in the matter. I rarely read fiction any more, but I find Tom Clancy interesting.

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