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Chapter Three:

BULLETS

You need something to hurl, in order to be shooting. Otherwise, you’re just making noise. But what bullets? What kind, weight and composition? The common, traditional bullet is lead. Lead has many useful attributes; it has a low melting point, high density, low cost (relatively speaking) and is easily shaped. It is, however, viewed in some circles as being highly toxic. Well, yes. But, “dose makes the poison.” Take the basic precautions and you won’t have a problem.

Lead bullets are commonly alloyed to make them harder, to allow them to fill moulds more readily and to adjust diameter. Diameter? Yes, if you take a bullet casting mould of any given diameter, the diameter of the bullets produced can change, depending on the composition of the alloy you cast in them. Unless you are going to do your own casting, that is a theoretical consideration. But hardness isn’t. To understand hardness and the need, let’s look at the bullet’s flight (the title of a very interesting book by Richard Mann, written in the 19th century and still relevant).

The powder charge goes off and the pressure slams into the base of the bullet. The bullet is pushed forward, exiting the case and then the chamber. If it is in a pistol, it slides right from the case into the rifling. If it is in a revolver, it has to jump out of the case, from the chamber throat, across the cylinder gap, into the forcing cone, and then to the rifling.

If the bullet hardness and the pressure are properly matched, the base of the bullet upsets, or obdurates, just enough to provide a gas seal. The bullet scoots forward, engages the rifling, spins and is on its journey. If the pressure is too high or the bullet too soft, the base over-obdurates, creating increased friction to the throat and rifling. It can also lead to a partially-molten bullet base, which is really, really bad. If the pressure is too low, the bullet won’t upset at all. The gas can sluice past the bullet, a process called flame-cutting. It will melt the sides of the bullet, producing leading and poor accuracy. A bullet that is too hard won’t obdurate at all, and will be similarly flame-cut.

Full metal jacket bullets usually aren’t, they have the base with the lead core showing.

This process is obviously affected by bullet diameter. If the bullet is too large, it will have greater pressure. (More resistance produces more friction, leading to more pressure.) A too-small bullet will flame-cut like a banshee.

So, when you are ordering your cast bullets, hardness is not the only thing to look at, and harder is not always better.

We also have the problem of multiple diameters to consider in revolvers. The bore of a barrel is the diameter of the rifling cuts, down to the bottoms of the troughs. Let’s use the .45 colt as an example, as it has been made for a long time and subject to a lot of changes. Until the 1950s, the common bore diameter of the .45 Colt was held to be .454 inch. With the rise in popularity of the .45 ACP, manufacturers drifted down to its bore diameter, .452 inch, as the standard for all .45-caliber firearms, ACP and Colt. So, you can have a Colt revolver from 1920 and a Colt revolver from 2010, and they can have different bore diameters. A 1911 from then and now is much less likely to wander.

But it gets worse, a lot worse. The portion of the chamber, forward of where the case rests, is smaller than case diameter. Called the “throat” in many circles, this should be the diameter of the bullet being propelled, or only a smidgen larger. It has, however, been all over the map. It is not uncommon to read of reloaders in decades past who measured their Colt to find the throat diameter at .456 inch, .458 inch or more. A .454-inch bullet, sluiced through a throat of .458 inch will lead, and it will arrive in the forcing cone already shedding lead. The throats will lead, the forcing cone will lead, the bullet will suffer grievously and accuracy will suck.

When ordering cast bullets, hardness is not the only thing to look at, and harder is not always better.

The usual first reaction to leading is “Ohm ygod, thebulletistoosoft” and then load harder bullets. Harder bullets in this instance will only make it worse, as the bullet flame-cuts just the same as the soft one did.

The solution is twofold: larger diameter, to match the throat if at all possible, and soft enough to obdurate at the pressures involved. “But, you can’t send a .456-inch bullet down a .452-inch bore.” You can if it is soft enough. And properly lubed. (In this instance, fat chance of finding a .456-inch bullet. You’ll have to cast your own.)

Or, use a lubed, hollow-base bullet and let it bump up to fill the throat and then squeeze down to fit the bore. As a final option, a new cylinder, reamed with throats of the correct diameter. This was a last resort choice, but done in the old days when there were more (typically for the Colt SAA) cylinders available, and fewer factory-new choices.

To diverge slightly, the solution was to take a leading-prone and oversized-throat .45 Colt, find an inexpensive .38 Special cylinder, and have the charge holes/chambers reamed out to .45 Colt and correct throats. Then the new cylinder would be fitted to the gun (setting back the barrel if need-be) and all was hunky-dory. It ended up costing twice as much as a new gun, but the accuracy was typically top-notch.

Lead bullets are not just cast, they can also be swaged. In swaging, lead wire is cut to proper lengths, and then the bullet maker uses hydraulic presses to simply squish the lead wire segments into bullet shape. Then the bullet is coated (usually with a dip or wash) with lube, boxed and sold. Obviously, a swaged bullet is a lot softer than a cast one, and thus more suited to low-pressure uses.

Plated bullets are truly full metal jacketed, but the nomenclature is either “plated” or “total metal jacket.”

The basic, century-plus old lead round nose, next to a jacketed hollowpoint.

JACKETED

Jacketed bullets won’t flame-cut, but they are not all that keen on obdurating, either. They will, but the pressures involved are typically a lot more than with lead bullets. Jacketed bullets offer many advantages – no leading, controlled expansion, higher potential velocities – but they do so at higher cost. Not always, but often.

Jacketed bullets come to us via two manufacturing methods: cup-and-core and bonded. In c-c bullets (jhp, soft point, and fmj*), the lead wire, as with swaged bullets, gets cut to length then slammed into an open copper or gilding metal (95 percent copper, five percent zinc) cup. The bullet is pummeled, squeezed, shaped and given a finish slam to keep things together, and that’s it. In an interesting aside, the last step of manufacture of cup-and-core bullets is to hydraulically press the core into the jacket. You see, gilding metal is springy, but lead isn’t. So, if you finish-size to diameter a jacketed bullet, the lead gets squished down, but the jacket then springs back. Granted, the spring is perhaps a ten-thousandth of an inch, but it is there. So, the lead core gets re-swaged back out to the jacket interior walls.

Under more-or-less normal use, the two stay together. However, when jhps actually expand, it isn’t unusual for the lead core and the jacket to separate, which is bad for terminal performance.

On the lead round nose, note the cylindrical bearing surface, and the rounded nose above. A good design (which this is) has them as separate components. Older designs had the round nose blending smoothly into the cylinder, and typically they didn’t shoot as well as this one does.

Cast lead bullets can also have a gas check. The gas check works like a set of copper galoshes, keeping the base of the bullet protected from the powder gases.

The truncated cone. The TC was the original 9mm Parabellum design, back in 1904. It suddenly became vogue in the U.S. with the adoption of the 40 S&W, in 1990.

Bonded bullets are those which essentially (each maker has their own proprietary process) the lead core is soldered to the copper/ brass jacket. They can’t separate. No matter how you peel back the jacket, the lead core will stay bonded to it. And the lead, being quite malleable, will stay attached to itself. Bonded bullets have a stellar record of expanding while remaining intact, even after penetrating intervening obstacles like windows, sheet metal and heavy clothing. But the process of bonding adds cost.

* jhp = jacketed hollow points; fmj = full metal jacket

PLATED

Plated bullets are made to offer the best of both worlds – lead and jacketed. The soon-to-be-plated bullet core is typically swaged to shape. Then, the bullet cores are dunked in a chemical solution, and while in the solution an electrical charge electroplates them with copper. The trick is to plate the bullets as individual bullets, and not just plate the whole pile of them into a copper-encased blob. How do they do it? I don’t know. They won’t say, and I don’t blame them.

The double-base wadcutter is a simple cylinder, and can be loaded in either direction.

The hollow-base wadcutter. The bullet is loaded base-down, and it acts exactly like a minié ball. The skirt expands to grab the rifling, and the nose-heavy design keeps it going straight. And yes, they travel a lot further than 50 yards.

One thing that I do know is that plated bullets can be very good, but they can have some quirks. The soft core has a soft plating, and the thickness of the plating makes a big difference in the final product. Thicker is better. Also, the plating process, since it has to use some method of keeping the bullets apart, ends up with bullets that aren’t as “crisp” as jacketed ones. However, that can be solved to a certain extent. One method of making plated bullets even better is a secondary swaging operation, often called a “double-strike.” There, the plated bullets are individually swaged to final dimension, and the swaging cleans up some of the vagueness of the bullet dimensions. You can recognize such plated bullets by the impact mark on the base, a circular pressed area.

The plated bullet is not a jacketed bullet, it is a compromise. It is meant to deliver many of the benefits of a jacketed bullet, at something closer to the cost of a cast lead bullet. The hardness/durability of the plated bullet depends on the alloy of plating, the thickness plated and the pressure used to double-strike the finished product.