Muzzleloader: Black Powder Scatterguns

Muzzleloader shotgunning is coming back into its
own in a big way. Rather than depending on the
rule-of-thumb “equal volumes of powder and shot,”
hunters are learning there is much that can be done
to improve patterns and performance.

Throughout our history, the perception has been that America is a nation of riflemen. From Bunker Hill to the present, we think only of rifles being used in military engagements. The fact is, however, from Colonial days forward America has lived with smoothbores. Indeed, it wasn’t until the War Between the States that a rifled gun was officially adopted as a military piece.

Similarly, during the nineteenth century, sport hunting was developing around the use of smoothbore muzzleloaders. As the country became more settled and civilized, hunting became a social and recreational pursuit, rather than a means of putting food on the table. All the sporting traditions associated with wingshooting arose during this period.

Today, many muzzleloaders are rediscovering blackpowder scatterguns. You can fine them in the uplands and in the duck marshes. Skeet, trap, and even sporting clays are all being shot with charcoal burners.

As recently as five years ago, someone hunting with a blackpowder smoothbore was a curiosity. Today you see them more and more often, and questions have turned from “You don’t really think you can hit something with that?” to “how can I develop a better load.”

As a practical matter, loading and firing a muzzleloader shotgun is simple. Think of the barrel as a shotshell hull you are going to reload. You drop in the correct amount of powder, cover it with an over-powder wad, drop in the shot, cover it with an over-shot wad, add a percussion cap, and ready, aim, fire!

Indeed, the basic process is so simple that many shotgunners give little thought to the components of the load. One writer has even talked about using an old hornet’s nest for his shotgun wadding, which makes me wonder if he’s ever actually fired a muzzleloader.

The fact is, there is no other firearm as component sensitive as a muzzleloading shotgun. Changing the over-powder wad from a ½-inch fibre wad to a ¼-inch nitro card, for example, can completely change both the pattern and point-of-impact of the shot.

Confusing things even further is the nineteenth century rule of thumb that you should use equal volumes of shot and powder when loading the shotgun. The equal volumes rule results in a load that gives acceptable performance in most muzzleloaders; but not necessarily the best performing one.

There’s a broad range of scattergunning components from which to choose. In addition to powder and shot, you’ll need an assortment of felt, fibre, nitro card, paper, and modern wads. Felt wads can be plain or impregnated with lube. And other components, such as the fibre wads, can also be used either dry or lubed.

You also might want to experiment with buffering your loads. Several materials were used for this in the past, plus you have the modern plastic buffers as well. Interestingly, I find plain white flour seems to make the best buffer, in some cases tightening patterns on muzzleloader scatterguns by as much as 20%.

If you measure your barrel you’ll discover the bore size is actually larger than its nominal classification. This is because the nominal bore is measured for a shotshell, which you are not using. So the nominal 12 gauge is more likely at 11; a 10 gauge a 9, etc. Double check before buying wad components. This is especially important for over-powder wadding, because if it’s undersized it won’t effect a good gas seal.

One problem you may encounter is trying to load a choked barrel. If components small enough to pass through the choke are used they won’t be bore sized. In the 19th century the British solved this problem with a “cup seal” wad---a waxed paper over-powder wad that looked something like the crown on a soda bottle. This gave them a dual diameter set up. The cup seal passed through the choking, but when it reached the powder, pressure from the ramrod caused the skirt to flare out and seal the bore.

Unfortunately, cup seals are no longer available commercially, so you have to either make your own, or use flexible bore sized materials such as lube impregnated felt to achieve that purpose.

Most modern blackpowder smoothbores are open choked for this reason, making them easier to load properly. On guns with screw-in chokes you can load with an open choke in place, then change to a tighter tube for actual hunting. Slower, to be sure. But it lets you build a more precise wad column.

Start your load development with a wad column as simple as possible. Using the manufacturer’s recommended powder charge, cover it with a ½ inch fibre wad. Drop an equal volume of shot and cap it with another ½ inch fibre wad.

Assuming you have an open choke barrel, pattern the load at 25 yards. Run at least five shots through your muzzleloader, using a full pattern test (30 inch circle with a 20 inch core) and examine it for total pellet count, density of pattern, and percentage of shot in the target area. Follow this with at least five rounds on a hunter’s pattern, which merely means firing at a life-sized outline of the game you’ll be hunting with that load, at the distances you expect to shoot. Here you are checking primarily to see how many pellets, on average, actually hit the game’s kill zone.

Next, slowly increase the volume of shot until the best pattern possible is achieved. This well be your primary or base load for that muzzleoader.

Your inclination will be to play with the amount of powder loaded. Although you can do this fairly safety with black powder because you will run out of shoulder long before you run out of powder room, higher velocity is likely to blow the pattern apart, rather than improve it.

Once you have your base load you can start experimenting with wad columns to see what sort of improvement is possible. The simplest second step is to split the fibre wads, using ¼ inch instead of ½ inch. Fibre wads split easily with just a fingernail.

As you experiment, only change one component at a time, otherwise you won’t know what affected any visible changes. For instance, do not go immediately to two ¼ inch fibre wads. Instead, leave a ½ inch over-powder wad and use a ¼ inch over-shot wad and see what happens.

Given the range of components, it’s easy to see how you can keep making changes for two days longer than forever. One thing you’ll discover early on is that over-shot wads rarely have significant effects on performance. There is one exception. Some wads can actually blow through the shot string, destroying the pattern. Sometimes, however, this effect can be good. If your goal is to open the patterns (perhaps for grouse hunting with a muzzleloader scattergun) that wad column can act as a spreader.

By and large, performance is most affected by over-powder wads. First and foremost create a good gas seal with a wad or wad column that can support the shot charge.

There’s nothing wrong with the equal volumes of shot and powder rule. Millions of rounds have been successfully fired that way. But developing the ultimate load for your muzzleloader is fun. And it insures peak performance on game or clay birds---which, when the smoke clears away, is the name of the game.