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CHAPTER 2 Black Powder to Breechloaders And the Transition to Smokeless

The origins of black powder are somewhat hazy. We know the Chinese had black powder or similar compounds, but used them only for fireworks, firecrackers and noise-makers. Using the force of the powder to propel a projectile just didn't occur to the Imperial Chinese military establishment. Either that, or having the many thousands of trained warriors and potentially millions of peasant conscripts already on hand, who needs noisemakers to scare the enemy? It took the dedication to war of the Europeans to develop this new technology.

Faced by a charge from these fellows, what infantry commander wouldn't want more firepower? Repeating firearms irrevocably altered the balance between mounted and foot soldiers.

In the centuries from the first use of black powder to the middle of the 19th century, experimenters had tried to come up with some sort of repeating mechanism. After all, in the military context, if some is good, more is better. If you could rain bullets down on your enemy, they couldn't cross the battlefield to meet you. (It can be positively depressing how many technical advances came from the need to gain an advantage in battle.) The problem wasn't the black powder, but the manufacturing methods. Getting a portable cartridge, and even a mechanism to feed it wasn't the problem. The problem was keeping the combustion process sealed away from the shooter. Doing so took two things, each precisely manufactured. First was the barrel, and second the repeating mechanism.

For a century now, barrels have been made from solid bars, bored and reamed, like this Browning barrel.

Many barrels, high-quality ones, were made by the Damascus method. Hand-forging a section of steel around a mandrel in a spiral pattern produced a good (for the time) barrel, but not one that could be mass-produced or produced to exacting, repeatable tolerances. The later method, employed by larger makers, of forging a barrel from a flat section of steel, punching it into a “U” shaped channel and then forging the seam produced more uniform barrels, but they were not much stronger. Without uniform barrels, you could not depend on the cartridges to seal the chamber on firing. Some early breechloaders, such as the Ferguson rifle, had a good seal. Developed just before the Revolutionary War, it used a spiral screw at the rear of the barrel. Turning the trigger guard rotated the screw down to expose the breech. It was accurate, reliable, sealed the breech well and too advanced for the British military. A later American attempt was the Hall. The Hall used a hinged and removable lock and breech assembly. By dropping each pre-loaded block into the rifle, a trooper could fire until his supply of pre-loaded breeches was used up. In a pinch, the removable block could even be used as a pistol of sorts. The problems with the Hall were fragility, poor gas seal, and the heavy weight of a supply of blocks.

Even from the earliest times, gunsmiths and inventors worked on breech-loading firearms. This is a breech-loading flintlock that uses iron or steel cartridges each with an integral frizzen.

The pinfire cartridge was an early attempt to perfect the enclosed cartridge. Each round has its own firing pin, which sticks up through a slot cut in the edge of the breech. The hammer strikes the pin, firing the cartridge.

Precision manufacturing allowed the use of cartridges made of brass instead of steel. Precision manufacturing also made the brass cartridges a tight seal against the combustion of the powder, increasing safety to the shooter. The impetus for the precision manufacturing was the American Civil War. The need for weapons, and ammunition to feed them, was greater than hand-production could supply. Machine-made firearms had the advantage of dimensional stability. That is, in order for all ammunition to work in all rifles of a given caliber, both the bullets and the bores had to be made to precise, and limited, dimensions. When a gunsmith was making his muzzle-loading shotguns one at a time a “12-Gauge” could mean his barrels were 12-gauge plus or minus .050” and no one would know. When reliable cartridges were designed and manufactured, a shotgun could not have a chamber smaller than the largest cartridge. If the chamber were too much larger than the cartridge, there would not be a proper gas seal. The advantage that troops using cartridge-firing firearms had over their muzzle-loading opponents was significant. A rifled musket could be loaded and fired four times a minute by a skilled soldier. He also had to stand up to reload. A soldier using a cartridge-firing rifle could fire at least twice as fast, and could do so, including reloading while prone. The Federal Army had to have cartridge firearms, and was willing to spend money to make the arsenals that could produce them. If cartridge repeaters had so much going for them, why was so much of the Civil War fought with muzzle-loading rifled muskets? Production, or rather, the lack of it. It does little good to equip an army with breech-loading rifles if you cannot provide them with ammunition. With arsenals set up to produce muskets and ammunition, the Federal Army would have been negligent not to use them. Because proven breech-loading weapons were available with ammunition to feed them, they were used. Some units even bought new designs out of their own pockets in order to gain an advantage.

Balancing the need for production against tactical advantage is not new. In 1543 English armories developed a method of making cannon barrels from cast iron instead of bronze. Cast iron is heavier, weaker and more brittle than bronze. And it rusts. When the tubes burst they shattered, creating casualties of the gun crew and adjacent soldiers. However, a cast-iron barrel can be made for a fraction of the cost of a bronze tube. Faced with the option of going to war with one company of artillery or four, for the same cost, what would you do?

After the Civil War the advantages of self-contained cartridges were so great that Colt did a brisk business converting cap-and-ball revolvers to fire cartridges. The same advantages applied to shotguns, and gunsmiths were quick to design breech-loading shotguns.

One design requirement of black powder flintlocks and percussion firearms was the need to keep the shooters face away from the breech. Unlike today, a shooter in the era before cartridge shotguns kept his head up, and away from the breech. To get the barrels up to his line of sight, the stock had to have an appreciable angle down, called drop. The drop in the stock created a lever to direct the force of recoil into the shooters face. Ever since cartridges have become common, stocks have gotten straighter.

Getting to today's plastic shotshells took quite a bit of work. Early shotgunners had a choice that many shooters today would think odd: The pin fire. In the early days of shotshell design, primers were not an easy thing to manage. Making the mixture (even coming up with an appropriate compound) was not easy. Getting enough into a shell to create complete combustion of black powder took more space than modern primers have. To maximize the use of the priming mixture, each shell had its own firing pin, resting directly on or in the priming pellet. The Lefaucheux system had many merits, primarily that it worked. Since shotgun makers were applying for design patents for breech-loading shotguns in the 1850s, the pinfire system came into common use and hung on for a long time. Remember, the shift to any new technology takes time, and in the pre-computer age it sometimes took a generation or two. As precise as manufacturing had become by the 1880s, primers were still expensive. If the priming compound was not evenly distributed in the cup, misfires and hangfires could result. I think pinfires also had a following (and for quite some time in Europe) for gunsmithing ease and shooter comfort.

And even after the pinfire was gone, the hammers would stay. Imagine yourself a gunsmith used to making a shotgun with external hammers (as black powder percussion and pinfire shotguns still would have been for decades by 1880). Or a shooter used to the visual safety margin cocked or half-cocked hammers represented. A shotgun that broke open in the middle and used self-contained cartridges was a shock for many older shooters in the 1880s. The hammers kept things familiar enough for both father and son to keep shooting even when the pinfire cartridge disappeared. Webly & Scott, shotgun and rifle makers in Birmingham, England, still listed double shotguns with external hammers in their 1914 catalog. I'm sure sales of hammer guns did not come back after the Great War. Anyone interested in shooting would not want to put up with such old-fashioned nonsense.

Military depots and gunmakers would test each batch of powder they received. If the powder did not register the proper power when fired in a test-gun like this, it would be rejected.

The shotgun shell was developed to hold a large amount of black powder. When smokeless arrived, the wad had to be changed to take the extra space left by the new more-compact powder. When steel shot arrived, there was plenty of room to adjust again.

Americans did not take to the pinfire in anything like the numbers that the Europeans did. I think it was the emphasis on breechloaders and ammunition capacity that crimped the pinfire's style. As much of a genius as John Browning was, I think even he would have thrown up his hands if Winchester had insisted on pinfire shells for a repeating shotgun. And if the ammunition companies were going to make centerfire shotgun shells for repeaters, then the makers of American doubles would just have to adapt to them. On both sides of the Atlantic, the pinfire was on the skids even before the next revolution, smokeless powder, came along.

Successfully developed by the French for their military rifles, smokeless powder was a wonder. It was compact, powerful, and produced hardly any smoke. It revolutionized military rifles and cartridges. In less than a generation, every major power and most of the minor ones had switched to a smokeless, magazine-fed, repeating rifle as standard issue. In the same time, many shotguns were blown up, and countless owners injured, maimed or killed. You see, black powder had some nasty habits, in that it was a low-grade explosive and could detonate in open air. A flame, spark or shock could set it off. But, used in a firearm or cartridge it had the comforting condition of being bulky for its power. You could hardly stuff enough black powder into a cartridge to make it hazardous to shoot. Black powder could be measured by volume, and the bullet or shot charge used to compress the powder on seating.

Smokeless powder is not an explosive but a flammable solid. In open air it burns fiercely but will not detonate. It is much more dense than black powder, and much more powerful. If you took the volume suitable for black powder in a cartridge and filled it smokeless, you would have created a bomb. Shooters and reloaders who were used to black powder had a difficult time creating enough fillers to take up the space difference. Powder manufacturers even developed special semi-smokeless and smokeless powders that were high-bulk and could fill the powder space in shotshells.

Even this was not enough for some shotguns. For centuries barrels had been made by the Damascus method. Two pieces of metal, one each of iron and steel, would be heated and hammered flat. The iron could be a common grade of scrap iron such as reclaimed horseshoe nails. (Could I make this up?) In an age of horse-drawn everything but railway carriages, leftover bits of horseshoe nails were common. The steel could be a good Swedish or German steel, or any tough and hard steel. The two flattened and clean pieces would be laid together, and the real hammering would begin. Heated and folded, heated and folded, the steel and iron would be layered many times, like a pie crust. Eventually the layered metals ended up as a rectangular bar. The bar was then heated and twisted in a spiral (with a lot more hammering) around a steel rod called a mandrel. As it was twisted the edges would be “welded” together. I use quotes because that was the term used at the time. The edges were actually forged together. The mandrel was then slid out of the finished tube. Once cool, the tube was filed, polished, reamed and turned into a barrel. For its time, and when used with black powder, a Damascus barrel was quite strong. For those who like the looks, it was also beautiful. The swirling, repeating pattern of the iron and steel would take blueing differently, and the pattern was obvious to any who saw it.

The pattern is also the weak point of Damascus. The edge between the iron and steel is a joint. Rust has a way of attacking joints. The joint is also weaker than the iron or steel even if it isn't rusted. The burning rate of smokeless powder created two problems for Damascus barrels. The peak pressure of smokeless is greater than that of black powder, and the rate of onset (the steepness of the upwards curve to the peak) is much faster. Smokeless hits harder and comes on faster than black powder, enough so that damascus barrels can rupture. Even if the pressure peak is kept down to that of black powder, the rate of onset is too quick and can still rupture a damascus barrel. The lesson learned then, and one that holds true today, is do not fire smokeless shells in a Damascus barrel.

To speed up the process, manufacturers looking towards mass production instead took a long flat section of mild steel (it was all mild steel in the 19th century) heated and fed it into a forge. The forge would stamp the steel into a “U” which was then finish-forged over a mandrel and the single seam “welded” shut. Much faster and cheaper to make than Damascus, it also produced a barrel more amenable to lathe-turning to final shape. Not until deep-drilling of steel rods became common did shotgun barrels lose their seams. In deep-drilling, a steel rod is drilled its length, and then reamed and polished to produce a barrel blank. Compared to the earlier forged barrels, a drilled barrel is absolutely uniform as a produced item. That uniformity greatly aided the development of reliable and safe breech-loading mechanisms. The new steel barrels were often referred to as “fluid steel” barrels. Not because the steel was more flexible, but because it came out of the crucible liquid, and was poured into molds to make ingots that were forged into bars, rods, rails and I-beams.

Damascus had been the mark of a fine gun for so long that some makers would take their new and stronger fluid steel barrels, and etch a Damascus pattern onto the outside. And you thought appearance for appearances sake was a late-20th century innovation.

While the strength drawbacks of Damascus eventually led to its demise as a barrel steel, the American emphasis on mass-production would have put the skids under it even without the advent of smokeless powder. (Damascus does seem to be making a comeback as a knife blade material.) As if the weakness wasn't enough, producing a Damascus barrel was more expensive. The many thousands of hammer blows it took could only come from a skilled worker, and his output was limited to a few barrels a day. Once created, the Damascus barrel had to be hand-filed, bored, reamed and polished. The iron and steel were each of a different hardness. Trying to turn a Damascus barrel on a lathe as a production process would have been a nightmare. With orders for thousands of shotguns, Winchester, Remington, Savage and the other large manufacturers could not even consider making barrels from Damascus.

Modern designs sometimes mean non-traditional approaches. Unlike the elaborate ejectors found on some doubles, this pump has an ejector that is just a sheet-metal tab in the path of the empty hull.

Damascus held on for a while in doubles, where mass-production was slower in arriving. One of the tricks of producing a double was in “regulating” the barrels. If you fasten the barrels together and to the shotgun parallel to each other, the center of the patterns of each barrel may not agree with each other. Trying to hit a fast-moving duck or goose is hard enough without having to remember “the left barrel is high and the right barrel is left” or some other mantra. Regulating the barrels in a double involves test-firing the shotgun before it is finished (termed “in the white” because it hasn't been blued yet) and adjusting the fit of the barrels to each other. The muzzle ends of the barrels are bent, tweaked and wedged until the center of each barrel hits to the same point at 40 yards. With all the hand work involved, the extra work of Damascus barrels is a small additional cost.

In the United States, test-firing shotguns (and rifles and handguns, too) is performed by the factory that made them. Considering the loss of business in the old days, and the potential litigation today, each factory is greatly interested in making sure each shotgun is properly designed and manufactured before it leaves. Things were (and are, for as long as they continue to have firearms) different in Britain. Centuries ago the established gunmakers found themselves competing against imports and cheap, shoddily-made local junk. To protect their customers (and to keep out the junk) they established “Proof Houses.” The London Proof House received its charter in March of 1637! The Birmingham Proof House received its charter in 1813. The job of the inspectors at a Proof House was to pass judgment on the safety of each gun presented. Once it had been measured and gauged, it would have a “proof load” fired in it. The proof load was a standard-size shell loaded to greater pressure than regular ammunition. After digesting the proof load, the shotgun was again measured and gauged. If no critical dimension had changed, it was deemed to have “passed proof” and was stamped as such. Even imported firearms had to go through the Proof House in order to be sold.

The British have never been into the high-pressure magnum ammunition that Americans seem to be enamored with. With sufficiently thick chamber walls and a low-pressure operating limit, British shotguns would last forever if properly treated. There was so much safety margin that many British Damascus-barreled shotguns were re-proofed with smokeless powder. Again, do not fire smokeless shells in a Damascus-barreled shotgun, even if you find British nitro proof marks on it. The operating pressures it was proofed to are probably lower than the standard pressures current American shotshells are loaded to.

The purpose of a proof house is to prevent poor-quality goods from being sold. And to protect a country's internal production capacity from imports. The “W” or “double V” is proof this piece passed inspection and test.

In the space of a generation, shotgun hunters went through a gantlet of choices. From muzzle-loading, percussion shotguns with outside hammers to doubles with internal hammers, automatic ejectors and shells we would recognize today. Or, for the real technology buffs, pumps and semiautomatic shotguns. And all the newest technology used smokeless powder. Reloaders had to try to keep up, switching from black, to semi- to high-bulk to smokeless powders.

Proper testing meant using a known ammunition. This Boulange chronograph that Fabrique National used to use is now on display. It took a crew of technicians to use this, test the firearm, and record and calculate the results. It's much easier today. Hooray for electronics!

One legacy of the change from black to smokeless is so puzzling and arcane that many shooters don't even try to follow it: the “Dram equivalent.” Many shooters simply go by brass height. “I need low brass” or “Pheasants take high-brass shells” and go with what they learned as kids. The convenient measure of black powder for shotgun was the dram. Certain combinations of powder and shot were found over time to most efficient, and the ammo makers settled on them. The “Three dram” load was 3 drams of black powder (obviously) and l-⅛-ounce of shot. If you think the choices today were vast, you should look into the catalogs of a century ago. It was common for hunters then to have the ammunition factory custom-load their ammo. If you ordered the minimum number (500, 1,000, 1,500 shells) you could have any safe combination of powder and pellets size and weight. If you thought that 3-½ drams of powder and 1-¼ of No. 4 shot was death on ducks (it was and still is) you could have the plant custom-make you enough to get you through the season.

When smokeless powder showed up, you couldn't just shovel three drams of it into a case or you would blow up any gun it was fired in. So the ammunition plants came up with the transitional “Dram equivalent.” By explaining the power of their shells in the language familiar to their customers, the ammunition makers planned to move completely out of the black powder business. What measuring scale was supposed to replace it? I'm not sure anyone knows, because the “transitional” measuring system is still with us over a century later.

And what a century it has been. Some things haven't changed much at all. Hunters still don't lead racing ducks and geese enough, and agonize over shot size and pattern density. Other things have changed radically. A pair of duck hunters camouflaged to their eyebrows, launching a duck boat from the trailer at the back of their SUV would be akin to men from Mars if seen by a duck hunter a century ago. And the radio-controlled paddling decoys? Wondrous stuff.

One good thing about the transition to smokeless powder was that it left us with a high-capacity hull and compact propellants. By using the extra space for cushioning, the shot-shells of today give their pellets a smoother ride than shotshells did back then. With the excess space that used to go to black powder freed up, the wad could be re-designed to protect the pellets. It also made possible larger payloads, which used to be devoted to extra pellets. Before the switch to steel shot, shotgun shells could be had with nearly 2 ounces of shot in them. Now, with the bulkier steel, payload weight is back down to what it was a generation or two ago. Again, the capacious hull gave designers, hunters and reloaders the room to work with.

When the Army adopted shotguns for use in the trenches, they adopted a new finish, Parkerizing, and full-length brass shells. Both the guns and the shells are now prized collectibles.

Oh, and the low and high brass? Another holdover, from the days of paper shotshells. Shells used to be assembled from paper tubes, base wads and crimped-on brass rims. The higher brass was for one of two reasons. The optimists held it was to keep the hull together under the higher pressure of a hotter hunting load. The pessimists felt it was simply a sales gimmick to get people to pay a lot more money for shells that only had a little more shot and powder in them. Today shells are made of plastic, and are molded or formed from a single piece. The brass (actually brass-plated steel) is there solely for the extractor to hold on to. Each type of hull made by a manufacturer has the same strength, regardless of how high the brass is. Some don't even bother with a brass rim, and have a plastic hull with a steel washer inside as support. If you are reloading, use what works and what the reloading manual suggests. If you are reloading but aren't using a reloading manual, get one and read it.

In the time before plastic the only way to ensure a water-tight cartridge was to make it from brass. The all-brass cartridge (left) is very expensive. For most uses, paper (2nd from left) worked just fine. Then came plastic. The high base is a factory indication of high velocity or heavy payload.