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View attachment 1826136

My best WAG.

The photo exposure began approximately 20 thousandths of a second after stuff left the barrel.

The duration of the camera exposure is approximately 1/1000 second. Point a1 is the location of the wad trailing edge when the exposure began. a2 is the leading edge of the wad at end of the exposure. Point b1 is where the slightly expanded fur ball of shot was when the exposure began. The distance between a1 and b1 is how far the shot was removed from the wad when the exposure began.

During the exposure the wad and shot were traveling at approximately 1,000-1,200 fps and would have traveled approximately 1-1.2 feet during the exposure which roughly appears to be the case in the photo when you extrapolate the length of the gun at approximately 4 feet.

The streak leading from the bore to a1 is a trail of “ejecta stuff” following the wad, hanging very momentarily in the still night air, highlighted by the floodlights /dark background and occurred prior to the photo exposure being taken.

b1-b2 is the shot “cloud” captured approximately 16-20 feet from the gun during 1/1000 second of flight. Approximately 2 feet in diameter and only beginning to transition from a ball of shot into a string several feet long.

a1-a2 is the flight of the wad recorded at a typical wad diameter of .75”, moving about a foot through the air and trailing the shot approximately 2’.
Look at the relative length of the wad streak (a1-a2) and the shot streak (b1-b2) taken with a camera shutter speed of 1/1000sec Note that I am using the same term to them (streak). What is the length of that wad? Maybe 2 inches (petals apparently still unspread)? From that, what can we deduce the length of the shots... maybe 3 inches? Even given an apparent disparity in luminescence (ability of an object to reflect light) between these two, we can see that the shots have barely separated from each other as measured from fastest to slowest, linearly, both "approximately 16-20ft" from the muzzle. A practical, real-life confirmation of the shot assessment is that when a person is shot with 1-1/8oz of birdshot at this range, his entrance wound appear like he's been shot with a slug.
 
The measurement of shot cloud length requires a sophisticated setup to say the least. Compton’s research showed the cloud length was so variable that meaningful conclusions were difficult to make. Here is a link from an article in Field & Stream dated 8/22/13 with actual measurements from Federal’s research lab - The Truth About Shotgun Ammo: 6 Questions Answered at Federal's High-Tech Range
Their measurement of the cloud length from a 12 gauge, modified choke, 1 ounce, 7.5 shot. 1235 fps at 40 yards was an average of 55”. They also pointed out the fallacy of Brister’s work way back when.
Ironically, premium shells have shorter cloud length compared to promo shells. In general, shorter also means better patterns.
 
Look at the relative length of the wad streak (a1-a2) and the shot streak (b1-b2) taken with a camera shutter speed of 1/1000sec Note that I am using the same term to them (streak). What is the length of that wad? Maybe 2 inches (petals apparently still unspread)? From that, what can we deduce the length of the shots... maybe 3 inches? Even given an apparent disparity in luminescence (ability of an object to reflect light) between these two, we can see that the shots have barely separated from each other as measured from fastest to slowest, linearly, both "approximately 16-20ft" from the muzzle. A practical, real-life confirmation of the shot assessment is that when a person is shot with 1-1/8oz of birdshot at this range, his entrance wound appear like he's been shot with a slug.
I would also opine with continued judicious approximation that the apparent travel distance of the shot in the photo seems to be a tad skosh more than that of the wad. Certainly to be expected at this point considering the relative rapid deceleration of the wad which lends parenthetic credence to the before mentioned wild assed guesstimated measurements. In agreement to your real-life shot assessment, I would offer the admittedly anecdotal observation that from across the dining room table and up to medium bar room distances, the shot stream, streak or string of a trap load will not be much larger than the pattern size and result in the onset of rigor mortise in a manner much like a load of buck or a slug.
 
The measurement of shot cloud length requires a sophisticated setup to say the least. Compton’s research showed the cloud length was so variable that meaningful conclusions were difficult to make. Here is a link from an article in Field & Stream dated 8/22/13 with actual measurements from Federal’s research lab - The Truth About Shotgun Ammo: 6 Questions Answered at Federal's High-Tech Range
Their measurement of the cloud length from a 12 gauge, modified choke, 1 ounce, 7.5 shot. 1235 fps at 40 yards was an average of 55”. They also pointed out the fallacy of Brister’s work way back when.
Ironically, premium shells have shorter cloud length compared to promo shells. In general, shorter also means better patterns.
Thanks for that link. This is the kind of stuff that puts the gun club porch talk to rest.

I would LOVE to see more detail on these tests. Method, equipment, numbers of takes. This is the kind of stuff I WISH I had available to do testing.

I am surprised that the shot strings are as short as they found. I was expecting more like 8-10 feet.

I would also love to see this same kind of work done for full chokes.

And I think they are absolutely correct, especially in trap shooting. Shorter is better.
 
This is the kind of stuff that puts the gun club porch talk to rest.
I certainly hope not!

The plethora of false information, lies and fairy-tales are the heart and soul of this sport.

Without it, no one would sit on the porch.





Shorter is better.

Oh sure, women have been lying to us forever saying the same thing.

What concerns me the most Tim is that you have bought into it.

But understanding your diminutive height challenged stature may have come into play, I will give you a pass on this one.

How do you say "Hey Shorty" in Portuguese?
 
The measurement of shot cloud length requires a sophisticated setup to say the least. Compton’s research showed the cloud length was so variable that meaningful conclusions were difficult to make. Here is a link from an article in Field & Stream dated 8/22/13 with actual measurements from Federal’s research lab - The Truth About Shotgun Ammo: 6 Questions Answered at Federal's High-Tech Range
Their measurement of the cloud length from a 12 gauge, modified choke, 1 ounce, 7.5 shot. 1235 fps at 40 yards was an average of 55”. They also pointed out the fallacy of Brister’s work way back when.
Ironically, premium shells have shorter cloud length compared to promo shells. In general, shorter also means better patterns.
Thanks for that link... average of 55" @ 40 yards. What could we deduce when premium shells have s shorter cloud length compared to promo shells? That the premium pellets have better uniformity compared to promo pellets? After all, we are paying premium dollars for them.
 
I would also opine with continued judicious approximation that the apparent travel distance of the shot in the photo seems to be a tad skosh more than that of the wad. Certainly to be expected at this point considering the relative rapid deceleration of the wad which lends parenthetic credence to the before mentioned wild assed guesstimated measurements. In agreement to your real-life shot assessment, I would offer the admittedly anecdotal observation that from across the dining room table and up to medium bar room distances, the shot stream, streak or string of a trap load will not be much larger than the pattern size and result in the onset of rigor mortise in a manner much like a load of buck or a slug.
Everything was quesswork based on the photo presented and so labelled.
 
Thanks for that link... average of 55" @ 40 yards. What could we deduce when premium shells have s shorter cloud length compared to promo shells? That the premium pellets have better uniformity compared to promo pellets? After all, we are paying premium dollars for them.
Harder shot, less deformation, better down range ballistics as a result. But I'm just speculating.
 
Or shoot a duck on the water about 60 yards away, You can see some shot arrive late with eyes.
What you see when you shoot at a duck on the water is just the pattern hitting the water. The bottom pellets of the pattern hit the water first below the duck and the top pellets of the pattern hit the water way farther out past the duck, just a little bit later.

2016-07-04 10.14.21 by https://www.flickr.com/photos/156463377@N08/, on Flickr

From KPY Shotshell Ballistics
1400 fps steel #3 shot is going 815 fps at 26.7 yards away, time .079 seconds.
1400 fps steel #3 shot is going 651 fps at 42.1 yards away, time .143 seconds.

I you shot at a duck on the water at about 34.4 yards and the bottom pellets hit at 26.7 yards away and the top pellets hit 42.1 yards away the pellets hitting the water at 42.1 yards would be hitting the water about .064 seconds later than the first pellets that hit the water under the duck at 26.7 yards away.

The pellets that hit about 26.7 yards away would be going about 815 fps and the pellets at 42.1 yards away would be going about 651 fps.
 
Everything was quesswork based on the photo presented and so labelled.
Granted, a level of WAG based on variables for a typical shotgun length of 48-52” and a trap load velocity of 1145-1200 fps. The shutter speed value was derived from a combination of several decades of empirical observations involving govmint paid for junior college level photographic course work and a whole lot of grain/pixel level examination of the effects of shutter speeds and camera movement on the acutance of a captured image. In combination with a simple ballpark computation involving the reasonably known velocity of the projectiles and the clearly delineated movement of the wad, I feel confident the values of this guesstimated photo interpretation are accurate to within ± 10% of what went down. Reasonably clear evidence that at this distance a shot string does not yet exist, derived from a level of guesswork at least 90% higher than making stuff up.
 
I certainly hope not!

The plethora of false information, lies and fairy-tales are the heart and soul of this sport.

Without it, no one would sit on the porch.
Or go on Shotgun World.






Oh sure, women have been lying to us forever saying the same thing.

What concerns me the most Tim is that you have bought into it.

But understanding your diminutive height challenged stature may have come into play, I will give you a pass on this one.

How do you say "Hey Shorty" in Portuguese?
Tim just needs to remember some of the girls in the bars there are less 'short' than he is. :sneaky:

Hi flabby dish towel?
Never heard the saying " Like stuffing a wet dishrag into a coke bottle."?
 
Tim just needs to remember some of the girls in the bars there are less 'short' than he is. :sneaky:
I lived in Thailand for 4 years. You really have to watch out for this in bars in Bangkok. 😱

Never heard the saying " Like stuffing a wet dishrag into a coke bottle."?
Nope... But I have heard "like trying to play pool with a piece of rope" and "like trying to push a rope."
 
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