Tuesday, June 29, 2010

A fresh look at defensive shotgun ammo and patterns

Gun and ammo makers have given a great deal of  attention to making shotguns pattern tightly, by the use of chokes and barrel boring tricks, and the construction of tight-patterning shotshells. This is all to the good, so long as we are shooting at ducks. I am dismayed to find the same techniques applied to defense guns and ammunition.  For the very short ranges that are usual in personal defense shooting, is it not progress in the wrong direction?

For defensive uses of the shotgun, we should instead demand barrels and shells that spread out the shot more, not less. If we accept the usual rule of thumb, that says the shot spreads about an inch for every yard it travels, when it is fired from a barrel without a choke, a felon at ten feet is facing about a three inch pattern. The pattern will, most likely, be smaller still, since the shot does not begin to spread until it separates from the shot cup. Wouldn't it be better if the pattern were bigger? It would give the home defender more margin for error.

It's rather frustrating to see the ammo manufacturers going in just the wrong direction. For example, Federal's FliteControl buckshot shells pattern tighter than any I have seen. In many guns they give patterns approaching half the normal size, and do it even in cylinder bores. That is amazing performance, and for some uses, just what one wants. For the typical, very short range scenario we are contemplating here, though, this answer is exactly wrong. Federal knows how go put a fast-opening pattern into a shotshell; they have done it before.  They used to offer a Premium Personal Defense load that was a spreader load of #2 lead shot. It was a marketplace flop but I thought it made perfect sense.

Of course it is a good thing when a company gives its customers what they want, but I conclude the customers want the wrong thing. If the goblin is ten feet away or twenty or thirty, shooting him with a tight pattern is too much like threading a needle. You lose the advantage of the shotgun, which is the margin for error that comes from the spread of the shot.

I do not mean to single out Federal here. They are just a convenient example. Other shotshell makers also boast of their shells' tight patterning, even in advertisements for their personal defense lines. It seems like they are bragging about something they should be ashamed of. It looks to me as if the excellent, tight-patterning technology developed for hunting has been applied, without much thought, to defense loads.

The only spreader shells I see for sale are loaded with very small shot and intended for bird hunting in close cover. Handload your own spreader buckshot shells? Please don't. You never want to use handloads of any kind for self defense, because some eager prosecutor is sure to say, "You see, ladies and gentlemen of the jury, the defendant didn't think ordinary storebought ammunition was deadly enough, so in his basement he contrived a super duper killing and maiming shell..."

So we are left to look to the other end of the barrel to see what improvements we can work thereon. Spreader chokes are available for guns that use interchangeable choke tubes. Briley, for example, offers a spreader choke called a "Diffusion" choke. The screw-in Polychoke has two settings claimed to work to spread the pattern. There are other muzzle attachments that likewise claim to spread out your shot.

But, inasmuch as shotgun chokes seem to function as much by arcane magic as by physics, people report mixed results. Some have found a spreader choke actually tightens their patterns, just the opposite of what is expected and desired. Others report the attachment does nothing, while still others get the advertised results.

It might be possible to very carefully expand a cylinder bore barrel to make a negative choke. We see here and here that some manufacturers' spreader chokes are just a .005" expansion.

Firing shot out of a rifled barrel spreads the shot but produces donut shaped patterns that are too big. Tip of the hat to Box O' Truth for this T&E. We see a common bit of misinformation put to rest here--firing shot loads from a rifled bore is not a workable idea.

No, what's really called for is a factory loaded spreader shell in some shot size appropriate to self defense use. I would think a fast-opening load of size T (.20") lead shot about right. I would buy a case, but if that is the only case of it the manufacturer sells, it is not worth their time to make it.

The problem here is the shooting public's unreflecting belief that tight pattern = good shell, something that is true enough in many contexts, but not all. Maybe by talking up the issue here I will start stirring up interest in, and demand for, a shotshell that really suits the home defense scenario.

3 comments:

  1. Does anyone know if the Spreader-shot shells damage your bore or chokes!

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  2. I haven't heard of problems with properly loaded spreaders. They've been in use for many years. Anybody aware of any issues with these things?

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  3. It seems that common sense is none too common these days.
    I just purchased a HD shotgun and am experiencing this issue. I'll never shoot at anyone over 10 yards in my house. If I wanted a small concentrated force to apply at an intruder, I'd use my AR. A HD shotgun should apply as much force possible with a wide pattern over a short distance.
    If I find a shell like this I'll buy a case as well!

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