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Discussion Starter #1
For discussion how long do you think the shot string is from a full choke gun
w/std 3 dram 12 ga shell at 40 yards?

Give me your answers or guesses of what you think they are.

If you think it is fact what was your source


Gary Bryant
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In his November 1979 article in American Rifleman, '(What is) the effect of a shot string?' Ed Lowry recounted his years measuring shot strings for WW. He found that the best way to counter the variability was to adopt a measure which was more consistent, settling on the length that would contain 80% of the shot.

In his numerical example that followed, he used an 80% length of 80 inches. Since I doubt he would have used numbers which were not representative of the data he obtained, I'll say an 80% length of 80 inches is a fair estimate of the answer you are seeking, Gary.

The article goes on to say shot-stringing doesn’t make any practical difference anyway.

Neil
 

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Discussion Starter #4
What would you say if I told you approx 16ft for 3 dram 1 1/8th oz #7.5s

Comes from gunsmithing school. That is the full length not 80%

Gary Bryant
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I would be incredulous of that answer. I like Neil's answer better.

Charlie
 

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That's interesting, Gary, but in your post you wrote:"If you think it is fact what was your source"

Did you offer the same challenge to the gunsmithing school and what was the answer? How did they get their 16 feet? Did they mentions Ed Lowry's work at WW? Did they know about it?

Their answer of 16 feet might well be true, the I begs the question "When do you stop counting?" Say most the shot got by in 10 feet, all but a few pellets by 12, and finally that last, lost, lonely pellet drifted by 16 feet after the first. Do you call that 16 feet? Ten or 12 is clearly more representative of a "practical" number, even though none of this is "practical" since it doesn't make any difference.

But even that last pellet system I just described is open to serious question. Really, any of them are.

What is being measured is not a photo of the whole shot cloud, but rather the scientist is noting the arrival of pellets at some specific point and calculating the length using the speed of the shot. But the speed is variable, particularly as relates to the last few pellets. Recall how in the Baker/Winston videos often the golden pellet which broke the bird was way, way, late, long after the main shot cloud went by. It had to have been going slower (That's why it was late.) So to be really accurate, the gunsmithing school would have to factor in the difference in average speed of the leading vs trailing pellets. Did you ask them if they did? What did they say?

Neil
 

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I've seen high speed photos of the ejecta leaving a barrel and just beyond, and while I do not have specific measurements I am pretty sure 16 feet is stretching it...
 

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The importance of shot string length is nil when compared to speed of targets and shot string. I'd say Ed Lowery comes closer in guesstimates of usuable length. A 40 mph target hardly stands a chance when pointed correctly with a 500 mph (approx) shot string?

Hap
 

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Discussion Starter #14
I would say the length of the mass is a better judge than first to last, but as it was explained up to 20 ft, but that was not a trap load he was using but Tungsten and larger shot dia.

But it does confirm what the Gunsmithing School came up with in their testing.

The farther the target is away the longer the shot string will be.

A realistic test would be a 32 yard target distance, and have not found any one that has done it.

It has to be done with a High Speed Camera at right angles to the shot string
and measured by ELAPSED TIME and SHOT SPEED to get the correct LENGTH @ 32 yards.

I just posted it for discussion anyway. It is like how far is the moon from earth? Almost 139,000 miles 138,600 is the last one I heard.

Gary Bryant
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Here's something to think about. Remember Bob Brister and his tests of shot strings using a long sheet of paper moving at 40MPH, driven by his wife?

The lengthening of the pattern on the paper was his measurement of shot string, though he was loath to put a number on it, as I remember. Just short, long, and longer.

Page 147 and following in Shotgunning, the Art and Science:

" I took (soft shot) shells, emptied the shot from them, and replaced them with 7 1/2 shot robbed from a popular trap load.

...

At the stationary target, pattern percentages leaped to nearly 80percent, an average of almost 20 percent improvement. The difference was even more dramatic in the moving target. The short shot load, remember, had strung pellets badly at 40 yards and 40 miles an hour . . . But the same shell with high-antimony trapload pellets in it threw a beautifully round patten at 40 miles an hour with an average center density between 70 and 75 percent."

(Above edited for clarity regarding the subject at hand.)

My reading of Brister's findings make me think that for trapshooting and using premium shells , the shot strings are shorter than commonly found in cheaper fodder.

I never found the huge difference in stationary targets (20%) the he reports, however.

The important thing to remember is that for trapshooters shorter shotstrings are best but the difference is so small that it can be ignored for practical purposes. If you do the math in the Lowry article, the resulting numbers are very, very small.

Neil
 

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I believe Major Gerald Burrard (about 90 years ago) figured out that the shot-string will cause you will lose 30% pellet density on a 40 yard, 40 mph. crossing target, with an IC choke. And about 13% loss with a full choke. Those sound like pretty good patterns to me. Shot-string might be a factor with #4 shot and duck hunting, but not so much with clays. JMO

Wayne
 

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Granted not seeing everything in the pattern but all patterns photographed with high speed cameras are just slightly longer than width of diameter.
 

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Hap,


I think you're basically correct about Ed Lowery's take on shot strings, but you reach exactly the opposite conclusion as him regarding the target's chances of being broken.


Saying that the effect of shot-string is not significant under our conditions, given the speed difference between target and shot...and saying the target doesn't stand a chance are two completely different things.
 

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Shoot it across water and see what you think. You'll be surprised how short it is. It's like nonexistent. Stand stationary and swing the gun like it's a hard left or right.
 
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