Wait a minute! Are you saying that just because Barbra Streisand used to be a good singer, her political views might not be the gospel truth and she might not be the one to lead me on the path to Nirvana? Whew! That's quite a relief. I was thinking I would have to donate my guns to the EPA or something.
Bullet goes to sleep mode
- Thread starter mike a
- Start date
Wait a minute! Are you saying that just because Barbra Streisand used to be a good singer, her political views might not be the gospel truth and she might not be the one to lead me on the path to Nirvana? Whew! That's quite a relief. I was thinking I would have to donate my guns to the EPA or something.
This is a better reminder of what's going on. I would add that epicyclic swerve describes the wobbling tip of a bullet and not the bullet's actual path. Also, the path deviations actually caused by this do not 'self recover' -ever.
There is no force to cause correction in any particular direction(much less magically back to desired target). It's illogical to suggest that the same energy that causes deviation would undo that deviation once it's damped out and gone(leaving no energy available to do so)..
So if 1/2moa of group opening deviation were observed, due to late damping of bad bullet release(for example), out at 300yds, that particular deviation could not decrease at any greater distance. It would just get larger & larger, continuing on each abstract deviation path.
I have always shot better in moa at distance, than at 100yds, with every gun I've had. But of course, it's not my guns.
My theory, can't prove it:
I think it's parallax. It seems much easier for me to identify the exact point of 'parallax removed', on a paper target, further out. At 100yds, while I get only somewhat close to this parallax removed point, my brain adjusts enough to see the target solidly resolved just as it can for a 'slightly out of focus' condition at 100yds.
But this isn't really good enough.
Any bit out of focus at 500yds is very obvious, and unacceptable. My brain cannot even try to compensate for it. So I can precisely remove parallax at 500yds.
Well, at least it seems this way to me and my corrected vision.
Well if you shoot enough you will see all kinds of phenomenon.
I always tune at 200 yards because I have seen bug holes at 100 shoot 2 to 3 inch at 200 many times.
I also had 5 shot groups at 200 be .500" outside to outside and could not touch a 700 yard target. I shot and shot. so I asked a few guys what the H*LL. they said what ya shooting, I told them and they told me what to load, so I did. next time out I hit the 700 yards target first shot and had a 4.5" 5 shot group..I don't shoot that load anymore but I still wonder about it. I had a 6 Dasher that in tough wind conditions was shooting high .100's to mid .200's at 100 yards(a borden smithed gun)..then I finally got mild to no wind conditions and I was like now we will see how well it can really shoot yea like .500 to .750's at 100 yards.. I had trouble keeping my dasher tuned.. reminded me of a 6PPC.
I think sometime wind conditions,air density ect can play a big roll on a given day to how the bullets yaw and stabilize at any range. I have seen several times a wind from right to left tighter group left to right can really have a big effect on the tune of the load.. I don't think that is a big secret. some one said just shoot what shoots best for you.
Wait then have you ever seen a rifle, load shoot way flatter trajectory than it should?
With a known velocity and BC..I have seen them be 6" flatter at 300 yards.
Maybe the exit velocity was at a upward muzzle vibration and the bullet was yawed upward and then a slight up draft or a down draft and how it was high..which gave what seemed to be a super flat trajectory.
I sometimes think down draft which would cause the bullet to tip more up then rising heat waves off the ground caused it hang longer..ah I just don't even think about it I just shoot...if your high act accordingly.
I always tune at 200 yards because I have seen bug holes at 100 shoot 2 to 3 inch at 200 many times.
I also had 5 shot groups at 200 be .500" outside to outside and could not touch a 700 yard target. I shot and shot. so I asked a few guys what the H*LL. they said what ya shooting, I told them and they told me what to load, so I did. next time out I hit the 700 yards target first shot and had a 4.5" 5 shot group..I don't shoot that load anymore but I still wonder about it. I had a 6 Dasher that in tough wind conditions was shooting high .100's to mid .200's at 100 yards(a borden smithed gun)..then I finally got mild to no wind conditions and I was like now we will see how well it can really shoot yea like .500 to .750's at 100 yards.. I had trouble keeping my dasher tuned.. reminded me of a 6PPC.
I think sometime wind conditions,air density ect can play a big roll on a given day to how the bullets yaw and stabilize at any range. I have seen several times a wind from right to left tighter group left to right can really have a big effect on the tune of the load.. I don't think that is a big secret. some one said just shoot what shoots best for you.
Wait then have you ever seen a rifle, load shoot way flatter trajectory than it should?
With a known velocity and BC..I have seen them be 6" flatter at 300 yards.
Maybe the exit velocity was at a upward muzzle vibration and the bullet was yawed upward and then a slight up draft or a down draft and how it was high..which gave what seemed to be a super flat trajectory.
I sometimes think down draft which would cause the bullet to tip more up then rising heat waves off the ground caused it hang longer..ah I just don't even think about it I just shoot...if your high act accordingly.
Last edited:
It is my understanding that a bullets precession cycles, due to having to realign itself with the overall drag vector in a crosswind, only happen upon first encountering the crosswind and balance out fairly quickly. And any aerodynamic jump or other effects caused by the precession cycles will change the trajectory in an angular fashion but in a static way, not continuing to increase like a constant blowing crosswind. just wanted to add to your statement, not critiquing.
I believe I have found a mathematic explanation for the phenomenon.
There is a linear relationship between distance and impressiveness of group size, where distance increases impressiveness also increases. Expressed as a formula where impressiveness is expressed as a function of x and mx is the slope of increasing distance, the equation would be:
f(x) = mx + b
Following this, there is a secondary effect with a strong exponential curve. Once we have solve for the f(x) impressiveness factor, we can calculate the likelihood that the underlying group size would be verbally recounted to others. As you can see, with the factors of increasing distance and decreasing size there is a rapidly increasing incidence of "bullseye summarization", or BS for short.
Combine this aggregate auditory data that the average shooter encounters with the underlying experiential knowledge that is the basis for all shooting and reloading practices, and we have a solid foundation with which to calculate the direct relationship between distance and the resulting group size in minutes of angle.
m = (y_2 - y_1) / (x_2 - x_1)
The net result gives us concrete proof that the phenomon is indeed true.
Mr. Litz, can I please have my prize?
There is a linear relationship between distance and impressiveness of group size, where distance increases impressiveness also increases. Expressed as a formula where impressiveness is expressed as a function of x and mx is the slope of increasing distance, the equation would be:
f(x) = mx + b
Following this, there is a secondary effect with a strong exponential curve. Once we have solve for the f(x) impressiveness factor, we can calculate the likelihood that the underlying group size would be verbally recounted to others. As you can see, with the factors of increasing distance and decreasing size there is a rapidly increasing incidence of "bullseye summarization", or BS for short.
Combine this aggregate auditory data that the average shooter encounters with the underlying experiential knowledge that is the basis for all shooting and reloading practices, and we have a solid foundation with which to calculate the direct relationship between distance and the resulting group size in minutes of angle.
m = (y_2 - y_1) / (x_2 - x_1)
The net result gives us concrete proof that the phenomon is indeed true.
Mr. Litz, can I please have my prize?
Keith Glasscock
Gold $$ Contributor
It's in the mail.
jds holler
Gold $$ Contributor
I have talked to a few guys who claim to hit anything out to 300 yards with their 17 HMR's, yet when I shoot with them they can't seem to put five bullets into an inch at 100 yds. -- The ONLY explanation for this must be the "sleeping bullet" theory. Lemme know if there's anything wrong with my logic. 
jd
jdDo you work for the Government? IRS?I believe I have found a mathematic explanation for the phenomenon.
There is a linear relationship between distance and impressiveness of group size, where distance increases impressiveness also increases. Expressed as a formula where impressiveness is expressed as a function of x and mx is the slope of increasing distance, the equation would be:
f(x) = mx + b
Following this, there is a secondary effect with a strong exponential curve. Once we have solve for the f(x) impressiveness factor, we can calculate the likelihood that the underlying group size would be verbally recounted to others. As you can see, with the factors of increasing distance and decreasing size there is a rapidly increasing incidence of "bullseye summarization", or BS for short.
Combine this aggregate auditory data that the average shooter encounters with the underlying experiential knowledge that is the basis for all shooting and reloading practices, and we have a solid foundation with which to calculate the direct relationship between distance and the resulting group size in minutes of angle.
m = (y_2 - y_1) / (x_2 - x_1)
The net result gives us concrete proof that the phenomon is indeed true.
Mr. Litz, can I please have my prize?
I've heard this before and have experienced smaller groups at 200 than 100
I chalk it up to my eye being better at aiming small at 200 . Kinda like shooting offhand at 20 power is a lot harder than 5 power even though the object is closer it magnifies your imperfections.
Another thought is that when thinking about a 5 shot 1 inch group at 100 I think everyone pictures the 5 shots emanating from a single point , therefore in order for that same group to be 1" at 200 the bullet paths would need to bend inward (impossible). But perhaps they don't all come from a single point and end up diverging to 1 inch . Maybe it's a bit closer to parallel for each shot than we picture.If it was possible to have 5 shots fired parallel to each other then 1" at 100 would be 1" at 200 or 300 and so on. I'm not suggesting this is the norm or an absolute ,but I believe parallax could cause this to a greater degree.
I chalk it up to my eye being better at aiming small at 200 . Kinda like shooting offhand at 20 power is a lot harder than 5 power even though the object is closer it magnifies your imperfections.
Another thought is that when thinking about a 5 shot 1 inch group at 100 I think everyone pictures the 5 shots emanating from a single point , therefore in order for that same group to be 1" at 200 the bullet paths would need to bend inward (impossible). But perhaps they don't all come from a single point and end up diverging to 1 inch . Maybe it's a bit closer to parallel for each shot than we picture.If it was possible to have 5 shots fired parallel to each other then 1" at 100 would be 1" at 200 or 300 and so on. I'm not suggesting this is the norm or an absolute ,but I believe parallax could cause this to a greater degree.
At the risk of being ostracised by the forum I provide some reading for the doubters:
http://www.nennstiel-ruprecht.de/bullfly/longr.htm#header_longranges
In other words, the maximum yaw angle, which occurs close to the muzzle, is damped out as the bullet moves on.
https://arxiv.org/ftp/arxiv/papers/1309/1309.5039.pdf
We have since employed this arrangement to document pitch and yaw early in flight, the damping of pitch and yaw, and the increased drag due to pitch and yaw early in flight.
Time to study up guys, this is a known phenomenon.
http://www.nennstiel-ruprecht.de/bullfly/longr.htm#header_longranges
In other words, the maximum yaw angle, which occurs close to the muzzle, is damped out as the bullet moves on.
https://arxiv.org/ftp/arxiv/papers/1309/1309.5039.pdf
We have since employed this arrangement to document pitch and yaw early in flight, the damping of pitch and yaw, and the increased drag due to pitch and yaw early in flight.
Time to study up guys, this is a known phenomenon.
Raythemanroe
Bullet Whisperer
I was at Brian Litz’s seminar this February up in Tustin, MI and one of the subject of his presentation was this “phenomenon”.
His presentation was all the testing that he had done to date seeing if it can be documented. The long and short of it is after very extensive testing, and trust me he did more than you can imagine, he could not find any definitive prove that it existed. I think this material will soon be published so I won't give too much of it away...
I also think that he has a standing offer to anyone who is confident enough of what he is seeing this to come up and “show him the goods”. The offer I think is he will pay for the trip if it can be proven. Sadly he has not found anyone to take him up on his offer – I think his comment was “crickets” when the offer was made…
Easy, sand bag at 100 and with a good gun shoot lights out at further distances..
Ray
memilanuk
Gold $$ Contributor
Actually, a number of us *have* spent an unreasonable amount of time reading on this particular topic. The question isn't whether the phenomenon (bullet stabilizing as it gets further down range) happens, its whether it actually serves as a justifiable excuse for bigger groups near vs far. Everything I've read indicates that the amount of 'wobble' is not enough to account physically for the discrepancy in group sizes; scope parallax or simply shooter error (focusing too much on the group, not the aiming point at closer distances where they can actually see the bullet holes) are much more likely.
Raythemanroe
Bullet Whisperer
I'll be the first to say it, I have experienced it.. I don't see how free recoil at 100 would improve accuracy at a 1000 yards.. Same trigger pull, everything the same, the set up is pretty solid leaving most shooter error out of the equation.. Brian can come to the World Open and I will supply the equipment for the test.. He can run the test to weed out purposely induced error.. The problem is getting conditions to support such a test..
Ray
Ray
Raythemanroe
Bullet Whisperer
I would suggest (Now here me out) that the measurement of MOA doesn't relate.. A Minute Of Angle ten shot group at 100 yards doesn't relate to a minute of angle (10.47") ten shot group at 1000 yards.. What I feel I and others are actually suggesting about certain high BC bullets is that at distance they are out performing the MOA mindset that we seem to measure performance by at distance.. If my gun and load combo shoot half MOA ten shot groups at a 100 yards but frequently shoots sub half MOA (5" or less) at 1000 yards, is .5"-5" somehow defying logic? I suggest that it is common and that many bullets perform well at distance even without mind shattering small groups at a 100 yards..
Ray
Ray
The known phenomenon is the reduced motion of the bullet tip wobbling through smaller pitch and yaw angles as the bullet flies down range. This "going to sleep" is not the same as the oft-claimed shrinking of MOA of group sizes (dispersion) as a bullet flies downrange.
The theory related to shrinking dispersion actually asserts that the whole bullet is flying in something of a corkscrew or helical motion, and that the diameter of the helix gets smaller with increasing range such that groups at 200 yards and out have a smaller angular dispersion (MOA) than groups closer. This is a different definition of "going to sleep" and it lacks any reproducible experimental support - it can't be repeated for unbiased observers in a way that rules out other possible causes.
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.