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Plastic Shells & Plastic Wads - Part 2

Activities and Exhibits

The simplest way may be the best way. If that's the case, then why are some things seemingly so complicated?

In  an article entitled “Plastic Shells & Plastic Wads - Part 1”,  I discussed the evolution of the modern shotshell and the benefits those components made to the availability of moderately priced shotshells. They also added greatly to the reliability of shotshells since we no longer had to be as concerned about the swelling of paper shells and the effects of moisture on powder. When primers are sealed and we have good tight and sealed crimps, modern shotshells are almost waterproof.

I recently read some words by Holt Bodinson, the former editor of Gun Digest and writer for Guns Magazine.

“What's intriguing about the shotgun shell is its size and tree complexity. First, the shell is large and cylindrical. You can pack a lot of interesting loads down that tube.

But secondly, the shotshell is more complex than, let's say, a round of .30-'06. It's a system made up of a series of subsystems than have to work in concert to deliver the charge within the strict pressure criteria required by relatively weakly breeched shotguns.

The exterior ballistics of a shotshell are among the most complex in ballistic science. Rifle and handgun ammunition pale in comparison.”

So when we are talking about shotshells we are talking about an inherently complex delivery system.

Maybe we should take a closer look at a shotshell and examine each of  its components a bit more closely. I'll define those basic components as the hull, the primer, the powder, the wad or wads, the shot charge and the crimp.

The plastic hull can be made from a variety of materials, using different types of plastic, with or without a metal base, commonly called brass but may in reality be made from a variety of metals and in various heights or even be made of plastic, as in the case of the Activ shells that were popular a few decades ago.

The primer pocket in a hull of one shell may differ in depth from that of another brand, the hull material of a given shell may be thinner or thicker than another shell and of course, the entire length of the hull may differ from brand to brand, even within the now standard 12 gauge U.S. lengths of 2.75”, 3.00” and 3.50” shells commonly available.

Primers can differ in intensity. Some are classified as mild and others as hot. All things being equal, which they seldom ever are, just changing from a mild to a hot primer can change pressure, burn rate and patterning of a given shot shell.

Generally speaking, powders may be classified as fast or slow burning. Those are very simple words to define the smokeless powder that is used in modern shotshells but it sets the stage for a further discussion of how powder influences the performance of a shotshell.

Wads may be the most complex component of a shotshell. The material from which they are made, their overall design, their stiffness or hardness, and other features of a particular wad may be more influential on performance than any other individual component.

The shot charge may be considered the most important component of a shotshell by many shooters since the weight of the charge and the material from which the shot is produced can greatly influence the end result of the shot. Many shooters praise or criticize the performance of a particular shell just because of the shot that it contains.

The last component of the shotshell in this discussion is the crimp. There are generally 2 types of crimps. Perhaps the most common is the star crimp that is seen on many clays and upland loads. The rolled crimp with an over wad of some type is now seen on several turkey loads and once was very common on many paper field loads.

Associated with the crimp and not often discussed is the degree to which the overall load is packed and just how tight all the components fit together. The exclusion of air from the shell greatly influences its performance.

In part 3 we'll discuss how all these components fit together and how each of them influence the performance of a shotshell.

Stay tuned.

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