Seeking wisdom

T

tylerw02

Guest
It is possible to agg better at 200 or 300 than 100, simply because of the way MOA works. However, is it possible to have a smaller extreme spread at extended ranges than at 100 and why or why not?

Just looking for some ideas...this topic came up in another forum recently.
 
Not sure what you mean about the whole MOA thing.
However it is possible to have a rifle /cartridge / load combination that exibits less spread at longer range than short range on a MOA basis .
The old British SMLE had beter accuracy at 1000 than 100 on a MOA basis.
It was called Positive Compensation or Flip.
Something to do with how the barrel acted that brought the bullets closer together at long range.
Mauser style actions dont seem to do it thank god.
 
yes, you can shoot a smaller MOA at 200 or 300yds than at 100yds but that is not the norm. I have one rifle that seems to shoot the same group at 200 as it does 100yds, the only problem is the 200yd groups are good but the 100yd ones leave a lot to be desired. As far as extreme spread goes (assuming that you are talking about velocity), you can not shoot a smaller extreme spread at longer ranges than you can at shorter, they will be the same. Just think about it, are bullets going to adjust their velocity closer to one another once they are already on their way? Just can't happen.

Hovis
 
?????????

I don't know about this thing where there are claims that bullets somehow find their way back together out at longer ranges. This defies the laws of physics. Once an object is headed in a certain direction, something has to act upon it to make it change direction.
It would seem that once the bullet is started off on a different course than the one before, (this starts with internal ballistics and ends the moment the bullet exits the muzzle), something would have to affect it to make it go back on the intended course.
We all know that conditions move bullets around. But I doubt there are any internal homing devices that cause bullets to hone in on a certain point.
As for the MOA thing, yes, in really good conditions, it is not uncommon for Competitors to shoot better aggs at 100 than 200. But normally, conditions dictate the aggs, and things are usually bigger at 200, when speaking in terms of MOA.
........jackie
 
I used the wrong word with extreme spread....I'm meaning the actually measurement of the group, rather than MOA.

Jackie, you're reflecting what I'm suggesting on the other forum, unless there is some form of seeker bullet, I cannot think of anything to suggest it could physically happen.

Repeatedly I've heard people suggest their rifle "shoots a smaller group" at 200 than 100. To deny the feasibility opens the door for a shady physics "lesson."

My simple explanation: "had that group been shot at 100 rather than 200, it would have been better and that bad 100 yard group would have been even bigger at 200."
 
I think what commonly happens is this, they fire a group at 100 yards that is 1 inch, then their group at 200 yards is 1.5 inches, then they are saying their rifle shoots better at 200 yards than 100 yards.
 
From a scientific standpoint, what Jackie said is correct. It appears this phenomena belongs in the list of ballistic urban legends. If someone shoots better at 200 meters, vs 100, they just shot a better group.

Assuming the bullet trajectory is straight, it is, as Jackie says impossible for an object to redirect without an external force. If wind were redirecting, the wind would have to change every shot, and move it the desired distance and direction. This is, however not impossible, but extremely improbable.

Assuming the bullet trajectory is curved (besides gravity), every bullet would have to curve in the same converging direction. this, again, is extremely improbable.

So, I'll refer to the second law of thermodynamics in reference to the question. In summary, energy moves from a higher state to a lower state, and in this instance from order to disorder.

The other one I've heard claims of, is a bullet is hight at 100, low at 200 and high again, at 250. Not likely.
 
groups 100-200-300 & MOA

Hello, I'm not a true BR guy, but I dabble in some accuracy shooting, and compete in 200 & 1000 yard matches. I mean, I don't have tons of experience & knowledge, like a lot of the posters do.
BUT, I can unequivocally say that I have a trued 700 6br 8-twist Krieger rifle that will absolutely not ever shoot 1's, 2's, or 3's at 100, but I have (on several occasions, often enough to show it's probably not just a good day - I don't have those) shot the same 100 yard load & several different loads into 5 shot groups at 500 yards going 1.3", 1.1"......and the like.
SO I'm not scientific enough to answer the question, but my 2 situations are repeatable enough that I think it's not the random, bizarre, low percent "chance" that it can't be a reasonable theory.
I thought I've read on this forum maybe a couple years ago that there are some scientific minds far better than mine that say that it absolutely does happen, a rifle and load shoot an inch at 100 & far less than 5 inches at 500, etc.
I know, it doesn't make "sense", and I know, everything MUST follow a rule.
But there are some "rules" that we sometimes just don't ? get.....
??
Steve Long.
 
Ok, coupla' things...........


Mythbusters is 'WAYYYY out of their depth on this one ;) so they ain't any help.......



But so is this guy on the aforementioned website.


To anyone who really DOES understand how a bullet flies THIS >>>> " this upward twist force or torque will result in the nose of the bullet yawing to the right. This yaw is called the "yaw of repose". This yaw in turn causes the bullet to steer a bit to the right (following the nose)." <<<< STATEMENT shows his ignorance of the subject.


A bullet does not "follow it's nose" and until folks can visualize this then "wind drift" and "aerodynamic drift" and "the fact that bullets drift HIGH to the left and LOW to the right" (sometimes termed "wind drift induced vertical dispersion) will be a mystery. Everyone seems to think that bullets fly on planing surfaces like airplanes and they DON'T!


Dude is 180degrees off in his analysis (actually only 178* off but who's quibbling ;) ) and is also completely wrong regarding decreasing MOA with range..............If he thinks that the difference he points out regarding inch group sizes and moa groupsizes is "subtle" then he really needs work on his social skills.



In short, the guy on the website listed, Chris Long, is full of hot air, he's right up there with the Nennsteil Rupprecht (sic, don' wanna' bother) website about "how bullets fly" for propagating low-grade highspeak mumbo jumbo.


Mayhap someone can prove me wrong??? I do have McCoy's book close to hand for reference so if anyone cares to ref Chapter 11 sect. 4 and walk me through how it "clearly support's" Dude's contention I'm game :)



LOL




al



Ohhh Yeahhh, Tylerw02, lissen to Jackie, he's the real deal.





Now, do folks regularly SHOOT smaller groups at longer range???


ABSOLUTELY!


In fact nearly every competitive bow or pistol shooter will confirm this, I'd 'WAYY rather compete at 50yds with my bow VS 15 or 20yds, I'll shoot smaller at 50 yards 9 times out of 10. This is in no way "mysterious".
 
Consider this: A bullet orients its point into the center of resistance. So, if there is a crosswind, the bullet will point a bit into that wind, and the accompanying drag will be so oriented, & move the bullet "downwind."

OK, consider this model:

For the first 100 yards, there is a 10-mph crosswind. The bullet orients its point into the wind, and drifts as you would expect. After the bullet has gone 100 yards (in the crosswind), either the wind stops, or the bullet is shielded from it for the next 200 yards. It will re-orient its point straight down range. This happens in about 1 revolution of the bullet, i.e., quickly. Nothing will change the dispersion from the wind already there, but no further (wind) dispersion will be added. So on this model, in terms of MOA, it seems that yes, the MOA at 100 can be greater than the MOA at 300. Nothing to do with the rifle or bullet, just the wind.

Reasonably unlikely scenario, though.
 
Oh, not again! It's only January and it's come up already. This subject has had more threads on the shooting Forums than "moly vs naked" and "will a 45-70 kill a deer".:rolleyes:

For those who believe that it's possible, do this simple test and report back. Set up two targets, one at 100 yards and one at 200, 300, whatever. Line them up so that your group will pass through both targets. Shoot a 5-shot group under good average conditions. Compare the group sizes and post your results here for all to see.

Ray
 
Jackie , It seems odd to me also but the English say it did happen with the old Lee Enfield SMLE and Im sure it was also reported in Precision Shooter years ago .
I heard about it much before that .
There was a guy in Australia I think , that had a special flexible bedding system for the " muzzel end " called a " Dean Floater " That capitalised on this trait. We don't know everything and lots of unusual things have been lost in time . The English say it was the reason that they were so hard to beat at fullbore prone at 1000 yards in those days.
Thats what the history books say anyway , so go figure . I have not seen it with my own eyes however.
 
seeking wisdom

Humm interesting'
Here's my Opinion via observation.
I had a barrel that shot consistently small at 200 yd and very small at 300
At 100 it also was just so so. The long pointy 8 3/4 ogive bullets were the answer. They weren't quite as stable at 100 yds. i changed to a 7 1/2 for 100 and 200 and the groups shrunk. when i shot out to 300 i went back to the point 8 #/4 ogives and shot an official screamer at that range.
I don't believe the pointy bullet was quite stable at 100. it was fine at 2 and 300/ i believe it's bullet shape that causing the problem. i would try different shaped bullets and see what happens.
 
Charles E,


I don't see your bullet "re-orienting it's point straight down range" but instead "re-orienting it's point on the center of it's (new) flightpath."

Am I missing something?


In other words, even if you back off from the tunnel mouth and shoot thru 100yds of exterior conditions into dead air you cannot do better than to MAINTAIN the dispersion induced by the conditions. Nothing can induce bullets to magically converge except sometimes the aforementioned "Flip" and then only on the vertical plane, just like a quarterback throwing two passes to the same receiver.....one of them a "bullet" and one a "lob"..........they both hit their target but only at one given yardage, after that the trajectories cross over and their measured dispersion rate is actually GREATER than before.


This is an illusion only, the true vertical dispersion is masked or compensated for by the muzzle "flip".


I guess variable crosswind and luck COULD as you say produce the same effect on the horizontal if you were a hind-feet weather vane shooter.....ya' just makes sure to shoot your slow rounds in the lulls!



LOL



al
 
It hurts to say this but Alinwa has struck a good point.
The only yardage they used the Lee Enfield rifles at was 1000 yds. only.
Then switched to Mauser actioned rifles for other distances.
It beats the hell out of me.
 
In other words, even if you back off from the tunnel mouth and shoot thru 100yds of exterior conditions into dead air you cannot do better than to MAINTAIN the dispersion induced by the conditions.
Click to expand...

What I'm saying is, yes, the amount of dispersion already in the flight will be maintained, but will not increase. So, if the bullet has "dispersed" one inch at 100 yards, it will be 1 inch at 200 yards, not two inches. That would be a reduction in MOA, though not in inches.

I could be wrong, but here is my thinking. We learned in high school physics that once a vector is established, it will take work to change that vector. The usual (& erroneous) understanding of wind is that is "pushes" the bullet, so on the erroneous model, if the wind stops, the force stops, and the bullet continues along that vector.

I think this is the basis for most people claiming that a wind near the muzzle has more effect on a bullet than a wind downrange.

What I'm suggesting is that's not a good model, but I could be wrong.

The reason it's not a good model is because the wind doesn't "push" a bullet. Drag "pushes" a bullet; wind just orients the drag. When the wind quits, the drag is still there -- the force applied to the bullet doesn't change, in other words, only its direction -- work is still being done.

So, if the range lies due north, and for the first 100 yards there is a west wind, the bullet will point a little bit westward, and dispersion will be eastwards. If the wind quits at 100 yards, the force (drag) acting on the bullet does change direction, and the bullet will point downrange (due north). There will be no change in the amplitude of the force, but there will be a change in its direction. So yes, there is a force acting to change the vector of the bullet.

The problem in this is that a bullet goes 100 yards in about .1 second. For the air mass to stop moving the next .001 seconds (about a yard) is just not going to happen; the air (wind) too has inertia. Maybe your example with the tunnel would show this.

What am I missing?
 
Conclusions, observations........

*Once a bullet leaves the barrel, it is on its own...there is no magical force that will cause the bullet to do what you want it to do.

*Once a bullet departs from its intended path, the best case scenario is that it will continue on its new path (vector). The further down range the bullet goes, the greater the distance between the intended and actual paths becomes.

*There are a number of forces that effect the bullet's path. The further down range it goes, the more of these forces it encounters.....therefore, it is less likely it will stay on course.

And........Some of us probably are more careful or try harder at 200 & 300.

Soooo.........

*Fortunately, every shooter on the line at a given match has to deal with the same conditions and variables...........the only real exception is range position, which is usually of considerable significance...

-Dave-:)
 
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