In a case of “looking for one thing and finding another” I found this quote from Phil Bourjaily, shotgun editor at Field & Stream, to be interesting. It’s from a 2019 article in F&S.

“When I had the Federal enginers pattern-test every gauge for me in an attempt to find out why the 28 gauge is magic, what we found instead was that the 16 seemed to be (the) real magic gun in terms of pattern efficiency.”

I’d like to know more of how Federal conducted the tests but I can’t find anything.

Have any of you seen the results of this or similar tests or done testing of your own? I even wonder how they defined “pattern efficiency.”

Stand by for incoming “square load” rhetoric.

No, don’t want to go there.

What I’m wondering is how would you even go about setting up an experiment like this? There are so many variables that would have to be eliminated to narrow the test down to just gauge that I can’t conceive of an objective way to do this. Assuming they tested 12, 16, 20, 28 and .410 and narrowed the loads down to a 3/4 oz load of equal pressure and speed you still have a bunch of other variables that would be hard (or impossible) to eliminate. And in the end you’d still be left with the original question: how would define your goal i.e. pattern efficiency?

Aside from the obvious average % of shot in a 30” circle at a given range , I guess you could grid your target and judge the kill potential by pellets per square.
That seems like a small effort for a reasonable return.
I just try loads through a new gun at clays and use what feels best.

Trying to score it on a static target doesn’t do much other than show a baseline level. Real use brings other factors, as you point out.

I guess that knowing that you have a dense pattern might provide some confidence in your gun.

There isn’t any magic to be found in a particular gauge.

Patterns bloom at a certain distance and their pattern efficiency (which I guess I would call eveness of distribution of pellets) declines rapidly.

I shot a couple sharptails against a snowy background last January, and I was surprised at how nice the pattern density was at 25 yards and how terrible it was at 35 yards based on the marks in the snow

The shot still had a lot of detritus on the snow and I picked up the wads from both shots, but really patterns are only good for a certain distance

Agreed.
Like I said, put a little effort into patterning just to see what happens at the expected ranges.
I don’t have the free time nor the patience for an extended patterning session.

I guess you could ask Mr. B. what tests and criteria they used.

Sounds like Federal rediscovered some things bird hunters have known for centuries, but no one can explain. Like, how does a 28 manage to kill so much better than it should, why is the 16 the best upland game gun, and why do people hunt with .410s? Some things just cannot be explained.

Some light reading for those with the inclination

David J. Compton, “An Experimental and Theoretical Investigation of Shot Cloud Ballistics”, 1996
http://discovery.ucl.ac.uk/1382490/1/396689.pdf

150 different 10 cartridge batches of loads were tested, and more than 2000 patterns analyzed.

These findings reinforce the attitude that many aspects of shotgun ballistics, especially patterns, have no satisfactory theory to predict or explain the effects of the internal ballistics of a gun on the downrange behaviour of a shot cloud. ie. it is magic

Summary. More detail starting p. 232

p. 155 “Three-Dimensional Representation”

The general shape of the shot cloud revealed that the pellets arriving first (leading edge) are located in the centre of the pattern, and the trailing edge pellets appear at the outer regions. The deformed pellets, collected at the outer parts of the pattern, travel at the trailing edge shot cloud. The well-formed pellets, associated with the pattern centre, are to be found at the leading edge of the shot cloud. With the greater associated deformation on pellets at the rear of the load, caused by the pressure in the barrel compressing them into the pellets above, a similar relationship between the pellets deformation and location in the shot cloud is seen in both experiments.

p. 160 The longitudinal distribution of pellets in the shot cloud at ranges between 20-50m was shown, via shot cloud length, to be unaffected when the internal ballistics of the gun, such as choke, were altered. However, from high speed photography it is known that the initial distribution of pellets is affected by the internal ballistics. Therefore it is assumed that the in-flight effects of the pellet become the more dominant factor, thus masking the internal ballistics effect, at ranges greater than 20m.

From the analysis of the shot cloud profiles it was established that the longitudinal pellet distribution is best described as a Rayleigh distribution.

Analysing the lateral distribution of pellets in the shot cloud it was established that there are two independent distributions, that is the horizontal (x) and vertical (y) pellet distributions. These two distributions were shown to be best described as Gaussian (“bell curve”) distributions.

Neil Winston made the point over and over that since pattern distribution was Gaussian, "patchiness" was random and the primarily determinant of pattern efficiency/quality, with the same choke constriction at the same distance, was simply the number of (high antimony) pellets in the shell.

Previous discussion here
https://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=496511

In Brister's book Shotgunning - The Art and the Science he delves into pattern efficiencies in all the gauges. In the chapter entitled The Case for the Small Gauge he writes, concerning Oberfell and Thompson's conclusion:

"The most significant conclusion about gauges in that publication (by O & T) was: "It is the shot load that kills, not the gauge"."

Later he writes:

"I have found their rule to come close to being correct with perhaps the exception of the 28 gauge, which simply kills better than it is supposed to."

And later in the chapter:

"Neil Oldridge of Remington Arms Company (where quite a few pattern tests are made) told me that there are two mysteries in shotgun ammunition he cannot fully explain. One is why the 28 gauge is so highly efficient for the shot load it throws and the other is why the 12 gauge pigeon load of 3 1/4 drams of powder and 1 1/4 ounces of shot will pattern beautifully in almost any barrel."

I remember that thread Drew, it was a lot of fun.

Stan, Brister is 'pre-Jones' data. And pre-Winston.

That's like pre-Copernicus astronomy, haven't you heard?


That's what I've been saying all along. This accounts for the well known 'bloom' of the shot cloud and limits the effective range of even the tightest full choke.

I know who Jones, and Winston, are. I think you meant that tongue-in-cheek.(?) Did they disprove anything that Brister postulated?

Anyway, I'm not quite ready to accept that Brister's work is outdated. When it comes to shotguns he's been there and done it.

Thanks, Drew, for finding and posting the link to that 2017 thread. Verrrry interesting.

I have shot hundreds of patterns on a pattern plate in everything from 10 to .410. Most were decent with a few just terrible and a few great. You learn a lot about gun fit, hold points and how patterns change over distance. I even learned that I needed to allow for shot drop at long ranges which many seem to think pattern expansion make it unnecessary. I learned that aimed shots and quickly mounted and shot shots were very different.

When you get to the .410 you will find loads which seem very effective look fairly bland or even borderline bad on the plate. Don’t worry about it. And when you see how small the pattern diameter is it will be hard not to try to aim it in the future. I’ve never found the perfect gauge, the perfect choke or barrel. I did come across a mod 1100 barrel which threw almost perfect patterns with everything from 9’s down to 2’s and from 7/8 ounce up to 1 1/2 ounce. But that was a rare barrel.

I love it when people start imploring math or magically properties to patterns. I’ve killed a lot of ducks with the 28, with lead shot in my youth, but never found the magic load. Lead was my magic along with reflexes of youth and a steady supply of ducks to shoot under 30 yards. So I read all these articles about patterns with interest but know there is no one answer. Just like today’s hyper velocity loads are the rage but when I pattern them they never look that great. Again the hope that math conquers all. Being able to have your point of impact be where your aim point is more important to me than the theoretical distribution of random pellets.

OTOH it does seem worthwhile to at least attempt to verify one's theories and earnest beliefs, or read the work of those that have done so.

Richard P. Feynman, Professor of Theoretical Physics at the California Institute of Technology; Albert Einstein Award (1954, Princeton) and The Nobel Prize in Physics, 1965
“It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it’s wrong.”

Surely You're Joking, Mr. Feynman!
“The first principle is that you must not fool yourself — and you are the easiest person to fool.”

That’s a fact Drew

We were taught, to “only see what is there, and not see what isn’t there…”

Truthfully, if a person makes that mistake, as soon as you submit it for review, somebody’s going to hand you your head. Ideas nowadays in whatever topic, get floated across the globe, and there are always people out there digging in, and checking your work.

One of my kids is a frequently published neuroscientist, there are peopleOn every continent that are desperate to show you that you were wrong. It’s what keeps science moving forward.

If the “science” is politicized, all bets are off. There is no honest way that most covid guidelines would pass peer review, none.

Sure Craig.
They are all lying self serving idiots.

Now is the time for the unsubscribe button.

Now, that is a "sentence" that is just hard to figure the meaning of, I don't care how much you fool yourself. Maybe a neuroscientist could decipher it ...........

I don't think so, but yes some are. Worship the the ever vigilant and safety driven for the peace of mind they meter out, then swing by petri dish grocery store for upland bird fixings? Just kidding, we trust the uber eats drivers for their impecable hygiene.

Stan, I think that CZ means that scientists are a highly competitive and critical bunch, delighted to pick holes in each other's arguments and data. Hence the self-correcting nature of science - if you are wrong, your colleagues will be delighted to point out your mistakes. Much better to find them yourself before publishing; it saves a lot of embarrassment. In a huge field like neuroscience, there are thousands of very smart people in Europe, Asia, and North America scrutinizing each other's work.

The book Sporting Shotgun Performance by Dr. A. C. Jones is the only work I find combining theoretical work with accurate experimentation. O&T's work just doesn't cut it. Read Dr. Jones if you haven't done so yet. I don't believe Jones left room for any "magic." One of the biggest 'BUGBEARS" for pre-Jones is lack of statistical analysis. Dr. J discovered that there is so much variation in patterns as to require a ten shot sample. Secondly, meaningful statistical analysis (by hand methods) is real time consuming - - - so time consuming that nobody did it. Note that Dr. J automated his analysis from photo capture of each pattern, computer analysis of each pattern and analysis of each ten shot data set. Read the book.

If you run into something you don't understand, ask and you will get an explanation.