I don't understand how chokes work to shape shot pattern..
- Thread starter Mr. Bjorn
- Start date
But, but, what about all those fancy wads they sell and tell us how great they are
Then there is the manufacturers of choke tubes to.
There are several things that come into play from the time one selects the shell they are going to use in thier gun to the manufacture of the gun to the barrel and choice of tube (choke).
It sounds complex, but it is simple enough.
Have you checked out google or you tube for an explanation?
Tight Chokes
Rob
More choke means a more constricted opening. A 'full choke' has only 0.040 inches of constriction, but produces about a 35 percent narrower opening than cylinder.
So yes, in effect, the shot cup is being 'squeezed' and the shot will hold together longer after the cup/wad is finally shed down range.
A full choke will produce a pattern containing an average of about 75% of the shot at a given distance as compared to cylinder producing only about 40%. Of course, these are broad generalities, so shot size, load, etc will affect results.
*sigh* I suppose I should have said I understand exactly the difference between chokes. What I did not understand was physically how the choke effects the spread pattern, considering that the shot never actually comes into contact with the interior of the barrel. All the chokes do is squeeze the plastic.
Thanks CV32, yours was a useful answer
Thanks CV32, yours was a useful answer
The shot, in its cup(wad), is pushed together by the choke, thus causing it to stay together longer after it has left the barrel. Squeezing it more or less determines how long. It doesn't have to and it's not a desired thing to have the shot actually touching the barrel. Mostly because it loses velocity at different rates.
Phat Eagle
CGN Ultra frequent flyer
- Location
- Fraser Valley, BC
Phat Eagle
CGN Ultra frequent flyer
- Location
- Fraser Valley, BC
It sometimes depends on the type and manufacturer of the slugs... Too many variables... I only use my cylinder bore bbl.
canucklehead
CGN Ultra frequent flyer
- Location
- Calgary, AB
All modern slugs will fit through a full choke. You won't get the greatest accuracy, but it will work fine. This has been debated and discussed to death - Some will disagree, but it's been proven by many on here.
I use IC or MOD for slugs.
I use IC or MOD for slugs.
- Location
- The Badlands
Tagged for interest....
Juicebox4321
Member
oh so you can... well very good, thanks for info
*sigh* I suppose I should have said I understand exactly the difference between chokes. What I did not understand was physically how the choke effects the spread pattern, considering that the shot never actually comes into contact with the interior of the barrel. All the chokes do is squeeze the plastic.
Thanks CV32, yours was a useful answer
Well, obviously my sense of humor was lost in my technical description of marketing.
From the Briley web site and it doesnt get any simpler than this ''Ok, so how does a shotgun choke actually work? Let us begin first with an easy metaphor, a child in out in the back yard playing with a garden hose. He discovers that if he puts his thumb on the end of the hose it goes further. That, kind of, is similar to what happens with a shotgun. Now for the scientific explanation by a nuclear engineer named Robert Hedrick. In a nutshell, his computer model and 35 years of research explains it in this way. There are two forces that tell the story; the mechanical properties while the shot column is in the barrel and the dynamic forces of nature that affect the shot column after it exits the barrel. When the shot column meets up with the choke it forces the column to squeeze tighter together; these forces are called radial forces. Once it is out of the barrel, wind resistance and gravity act on it. When the wind comes into contact with the outside pellets of the shot column it induces spinning and they start to flare off like a ping pong ball with english on it. The tighter the choke the heavier the radial forces, the tighter the pellets are squeezed together so the pattern holds tighter over a longer distance. Conversely, the less restriction you have in the shotgun choke the more loosely the pellets are held together and the faster the pattern opens up.
There you have it! You now know more about shotgun chokes than 98 percent of the shooters in the world.
Cliff Moller Briley Mfg''
From a leading manufacturer of shotgun chokes for target shooting and hunting.
Best Regards,
Rob
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I gotta ask.. where do you get your info???
The shot cup has little to do with the end result of the choke; it's only a convenient way of loading the round at time of manufacture and stopping the pellets from rattling around in the barrel when fired. The single most important function of the wad is forming the seal between the expanding gases and projectile as a result of ignition from the primer and preventing it from leaking out around the projectile making it inefficient. The very first restriction happens at the forcing cone of the barrel when it is first fired. The choke at the muzzle end creates a determined amount of restriction which directly affects how far the shot string travels before separating.
My experience agrees with Briley and previous posters, with one caveat:
It appears to me that the concept and the execution of chokes employing barrel constriction was a technology developed during the felt wad era. Shot shell manufacturers have developed specialized "spreader" shells, or "distance" rounds, both based on shot cup variations. Most shot cups, though, are designed not to interfere with the gun's chokes.
I have never found a reliable way to predict patterns achieved with various combinations of shot shells with plastic shot cups and a dizzying variety of gun makers and fixed or screw-in chokes - aside from patterning itself.
For target shooting, I always use the same U/O gun and the same commercial 24 gram loads (with shot cups).
For hunting, I prefer using traditional 2 1/2" shells with felt wads and classic side-by-side field guns.
No science behind those choices, just personal preference. It would be interesting to do a full patterning board comparison.
It appears to me that the concept and the execution of chokes employing barrel constriction was a technology developed during the felt wad era. Shot shell manufacturers have developed specialized "spreader" shells, or "distance" rounds, both based on shot cup variations. Most shot cups, though, are designed not to interfere with the gun's chokes.
I have never found a reliable way to predict patterns achieved with various combinations of shot shells with plastic shot cups and a dizzying variety of gun makers and fixed or screw-in chokes - aside from patterning itself.
For target shooting, I always use the same U/O gun and the same commercial 24 gram loads (with shot cups).
For hunting, I prefer using traditional 2 1/2" shells with felt wads and classic side-by-side field guns.
No science behind those choices, just personal preference. It would be interesting to do a full patterning board comparison.
Been curious about this for a while. Specifically I see ads for "Black Cloud" or "Prairie Storm" chokes to go along with their respective Federal ammunition. Always wondered how/if these actually increase the performance of the ammo or if they're just a marketing opportunity.
