spin stabilization of projectile--yes or no?

stagpanther · August 1, 2022, 04:18 AM

This subject came up here a few years ago--specifically, do some bullets show a propensity to actually get better accuracy past the "standard" test range of 100yds? I've read in Litz's books that he believes this does happen in some cases and I think that was the argument being made at the time here. At the time, I scoffed at the idea thinking it was an impossibility. I've heard the idea of gases exited at the muzzle cause a disrupt--which I find plausible--it was the "centrifugal self-correction" part I had trouble with.

Well, some time has gone by and I've shot a lot of bigger magnum type cartriges--and--spoiled as we are as shooters--a whole new breed of ultra-high BC bullets have come out as well for these bigger cartridges. I've actually come around to the idea that some cartridges do in fact get better results when tested at longer range than 100 yds--like my 338LM, 7mmSTW, etc. It's gotten to the point where I don't bother developing loads for the big ones under 200 to 300 yds.

Your experience/ideas?

Bart B. · August 1, 2022, 09:56 AM

If slower bullets leave at higher angles to the line of sight than faster ones, their trajectories will cross trajectories of faster bullets at some point down range. Long, skinny barrels wiggle more in the vertical plane than short, fat ones

Weights (tuners) on the barrel at the muzzle move back and forth change the bore axis vibration frequency so slower ones do that. .22 rimfire match rifles often have them and have different settings for each range of 50 feet, 50 and 100 yards and meters. Highpower match rifles have settings for several ranges to 1000 yards.

Check out these websites.....

https://www.varmintal.com/apres.htm

http://www.geoffrey-kolbe.com/articl...vibrations.htm

Sierra used to test at 100 yards but changed to 200 yards several years ago. Their match bullets have to shoot under half an inch extreme spread.

stagpanther · August 1, 2022, 01:20 PM

Thanks for that Bart. If I understand the information in the link correctly, it more or less says that there is an optimal moment for a bullet to leave a barrel at a certain velocity relative to the degree of the barrel's whip to attain best consistency? I take that to mean this really has nothing to do with any notion of the projectile's spin causing the bullet to destabilize and then subsequently "restabilizing" itself?

Metal god · August 1, 2022, 01:29 PM

I think the question needs to be better defined for me to understand . I remember that thread and could not except that the bullet changes direction between muzzle and 200yds .

What I was hearing in that thread for example but was not actually said this way . This assumes bore axis and POA are dead on when bullet leaves muzzle . A bullet leaves the muzzle at a 2* off center of POA and bore axis and at some point between muzzle and 200yds that trajectory changes from 2* to 1.5 or 1* off axis .

Ok a body in motion stays in motion until …. So what is being said is the spin on the bullet is the “other” force acting upon the bullets trajectory changing it’s trajectory ?? Even if I agreed which does in fact seem plausible . Wouldn’t that mean that action could only go in one direction . So if the spin of a bullet causes it to pull to the left and you shoot a tad right it “may” pull it back to the left . What happens when you shoot to the left a tad to start with ? Are we now saying there is some force while the bullet is in flight to not only act against the initial straight line trajectory but also act against the second force of spin drift pushing it to the left as well ?

Jim Watson · August 1, 2022, 03:23 PM

What Bert describes is what I have seen called "compensation." The Lee Enfield was particularly well known at Bisley for twanging its barrel so as to bring bullets of different velocity to the same elevation at range. I recall mention of it all coming together at 600 yards.

This is entirely different from the legend of bullets "going to sleep" downrange and yawing less which somehow automatically causes them to converge on the center. Nope.

stagpanther · August 1, 2022, 03:38 PM

Quote:

This is entirely different from the legend of bullets "going to sleep" downrange and yawing less which somehow automatically causes them to converge on the center. Nope.

Actually the opposite--the bullet left the muzzle "dazed and confused, wobbling about, but then woke up further downrange and walked straight."

--and I too found it unequivocally impossible--and yet, especially with powerful magnums shooting big aerodynamic bullets, I have seen a tendency for groups at 2 to 300 yds group tighter than 100--though not all the time.

jmr40 · August 1, 2022, 04:10 PM

If I understand correctly the question is something along the lines of; Is it possible to have a rifle that will shoot at best 1.5 MOA at 100 yards, but then shoot 1 MOA at 200 or 300 yards?

That does not mean the rifle will shoot smaller groups at 200 or 300 than at 100. 1.5 MOA at 100 yards is roughly 1.5". One MOA at 200 would be 2" and 1 MOA at 300 would be 3". In rare cases I have observed this. But I've never seen a rifle that would consistently shoot smaller groups at longer ranges than shorter ranges. I don't see how that would be possible.

Virtually all of the time accuracy at all ranges is pretty predictable based on 100-yard accuracy. At least up to a point. MOST rifles/loads that are 1 MOA at 100 will be 1 MOA at 200-300 as well. Once you get much past 300 yards things usually open up. A rifle that shoots 1 MOA at ranges 300 or less may or may not be that good at 500 yards.

Whether or not this is real, or just a case of shooters aiming more precisely at long range is hotly debated. The last that I read about Litz was that he did not believe this phenomenon was real. But he may have changed his mind.

All I can say is that I've observed this a few times and don't know why. Maybe it was just a fluke, it doesn't happen often. But the times I observed it, it appeared to be with an individual rifle. Cartridge, load, or caliber didn't seem to matter.

Jim Watson · August 1, 2022, 04:32 PM

I recall the Brian Litz challenge. Your rifle, your ammo, his range.
Shoot through a thin paper target at 100 yards, in line with another target at 300 yards.
Can you make the SAME BULLETS land closer or even relatively closer at the longer target?

I once read posts by a guy who had set that up with an Oehler Acoustic Target. Never did get convergence.

hounddawg · August 1, 2022, 05:24 PM

Quote:

Originally Posted by Jim Watson

I recall the Brian Litz challenge. Your rifle, your ammo, his range.
Shoot through a thin paper target at 100 yards, in line with another target at 300 yards.
Can you make the SAME BULLETS land closer or even relatively closer at the longer target?

I once read posts by a guy who had set that up with an Oehler Acoustic Target. Never did get convergence.

that was in 2015, as far as I know no one ever has. Here is the link to the thread where he issued that challenge

https://forum.accurateshooter.com/th...lenge.3861880/

Quote:

The Applied Ballistics 'Shoot Thru Target' Challange
I'm inviting any shooter who has a rifle which exhibits non-linear dispersion to the Applied Ballistics Laboratory in Michigan to demonstrate the effect. I'll pay your travel and hotel stay (If you successfully demonstrate the effect, I'll even pay your *return* travel as well

) The objective is to produce a repeatable example of this phenomena so it can be studied and hopefully we can learn what's going on, and if it's how bullets really fly, or not.

Bart B. · August 1, 2022, 05:48 PM

Quote:

Originally Posted by stagpanther

Thanks for that Bart. If I understand the information in the link correctly, it more or less says that there is an optimal moment for a bullet to leave a barrel at a certain velocity relative to the degree of the barrel's whip to attain best consistency?

Yes. https://diprecision.com/ec-tuner-1/

Metal god · August 1, 2022, 06:41 PM

I was wondering how Bart enjoyed his free flight and hotel when he went to prove this can happen .

zeke · August 1, 2022, 10:08 PM

Quote:

Originally Posted by Metal god

I think the question needs to be better defined for me to understand . I remember that thread and could not except that the bullet changes direction between muzzle and 200yds .

What I was hearing in that thread for example but was not actually said this way . This assumes bore axis and POA are dead on when bullet leaves muzzle . A bullet leaves the muzzle at a 2* off center of POA and bore axis and at some point between muzzle and 200yds that trajectory changes from 2* to 1.5 or 1* off axis .

Ok a body in motion stays in motion until …. So what is being said is the spin on the bullet is the “other” force acting upon the bullets trajectory changing it’s trajectory ?? Even if I agreed which does in fact seem plausible . Wouldn’t that mean that action could only go in one direction . So if the spin of a bullet causes it to pull to the left and you shoot a tad right it “may” pull it back to the left . What happens when you shoot to the left a tad to start with ? Are we now saying there is some force while the bullet is in flight to not only act against the initial straight line trajectory but also act against the second force of spin drift pushing it to the left as well ?

Don't remember anyone describing the bullet changing direction, except some who instantaneously translated what was being described. Bullet yaw has been described as = "Yaw refers to the rotation of the nose of the bullet away from the line of flight". This means the bullet tip and bullet base were not rotating exactly inline with the center. The trajectory is not changing directions. Bullet yaw is not a new concept by any means.

Am of belief most any high speed projectile from rifled barrel has some degree of yaw to it, however minute or brief lasting. It becomes more noticeable with long bullets in slow twist barrels, which could become un-stabilized to point of tumbling. Some believe this is the reasoning for switching to faster twist rates for longer bullets, so they would not be "overstabilized". (edited because got slow and fast twist reversed)

Have personally experienced better accuracy at an increased distance with Sierra's newer 175 gn tmk through a Sig ssg 3000, and a Rem 33 gn vmax tipped 22 mag through an older cz. And no , am not saying the 175 gn load kept getting more accurate at each increasing distance. But it did have a noticeably better moa at 300 than 100.

Some also believe the british 303 round/rifle combination was made to easily tumble when hitting something, by not having the bullet fully stabilized at common distance.

Edited to change 22 lr to 22 mag, and identify specific bullet

Metal god · August 1, 2022, 10:32 PM

If a rifles best group at 100yds is 2moa and yet at 300yds it can shoot 1/2 moa . The bullet “is” changing direction between 100 & 300yds . Furthermore my point that “if” the bullet did yaw or whatever it would only be in one direction. As my example pointed out all shots to the right of POA may come back left a bit but shots left of POA would go further left do to the spin/yaw . Meaning you’re still not going to shoot better groups if all shots at zeroed on POA , at least not consistently

stagpanther · August 2, 2022, 02:46 AM

Well, I do have deteriorating eyesight and it does make sense that perhaps I'm just concentrating better at the longer distance than 100 yds.

zeke · August 2, 2022, 06:00 AM

Quote:

Originally Posted by Metal god

If a rifles best group at 100yds is 2moa and yet at 300yds it can shoot 1/2 moa . The bullet “is” changing direction between 100 & 300yds . Furthermore my point that “if” the bullet did yaw or whatever it would only be in one direction. As my example pointed out all shots to the right of POA may come back left a bit but shots left of POA would go further left do to the spin/yaw . Meaning you’re still not going to shoot better groups if all shots at zeroed on POA , at least not consistently

Bullets spin around an axis, they don't "change direction" or "corkscrew". What people describe as bullet yaw is the front and rear of bullet rotating in a slightly larger circle than the middle, while still rotating around the same axis, till the bullet stabilizes or becomes completely unstable and tumbles. This may be most easily observed with the much longer bullets used in sub sonic loads for the 300 blackout. Have experienced Nosler's 220 gn BT show oblong wholes in target at 25 yds from short barrel with too slow a twist. And yes, the short barrel likely contributed.

As an old red neck once said, "In order to learn something, you must first admit you don't know it."

Also don't remember any one saying the difference was 2 moa to .5 moa.

Changing the twist of a guns rifling to suit a longer or shorter bullet is to stabilize the bullet.

zeke · August 2, 2022, 07:53 AM

For those unfamiliar with projectile yaw, consider googling army testing of projectile yaw. They have been studying "yaw" for decades, mostly for maximizing armor penetration in artillery /rifle rounds.

Metal god · August 2, 2022, 10:26 AM

I know what yaw is and that is/was not my point . Even if the bullet is crazy unstable/yawing out to 100yds then settles down and flys perfectly straight from there . The group at 300 yards is not going to be smaller then the best groups at 100 , is all my point is . I don’t care if the bullet is tumbling out to 100yds then Stabilizes and flies true after that . The group is not going to be better at 300 then the best at 100 unless the bullet changes it’s trajectory/direction between 100 & 300yds .

If the bullet can shoot a smaller group at 300 then it does at 100 . It would be reasonable to conclude the groups will continue to get smaller the further the bullet travels ?

Are you saying the yaw effect has a constant and reliable effect that reduces group size the further out the bullet travels.

hounddawg · August 2, 2022, 10:47 AM

Newton’s first law is the the law of inertia. Newton’s first law states that if a body moving at a constant speed in a straight line, it will remain at rest or keep moving in a straight line at constant speed unless it is acted upon by a force.

We know that bullets drop because of gravity, and the speed changes because of wind resistance. Wind will affect the straight line but that is random and chaotic at best and impossible to duplicate shot after shot, group after group.

Until little thruster jets are built into bullets I would have to call convergence theory to be fertilizer produced from the digestive tract of a male bovine

zeke · August 2, 2022, 12:58 PM

Quote:

Originally Posted by Metal god

I know what yaw is and that is/was not my point . Even if the bullet is crazy unstable/yawing out to 100yds then settles down and flys perfectly straight from there . The group at 300 yards is not going to be smaller then the best groups at 100 , is all my point is . I don’t care if the bullet is tumbling out to 100yds then Stabilizes and flies true after that . The group is not going to be better at 300 then the best at 100 unless the bullet changes it’s trajectory/direction between 100 & 300yds .

If the bullet can shoot a smaller group at 300 then it does at 100 . It would be reasonable to conclude the groups will continue to get smaller the further the bullet travels ?

Are you saying the yaw effect has a constant and reliable effect that reduces group size the further out the bullet travels.

Again, no one except you said the group was smaller at 300 yds. What was said was accuracy was better, and smaller moa. To simply explain this, a 1 moa group at 100 yds is 1 inch. A .75 moa group at 300 yds is 2.25 in. While the 2.25 in group at 300 yards is physically larger, it represents better accuracy.

zeke · August 2, 2022, 01:06 PM

Quote:

Originally Posted by hounddawg

Newton’s first law is the the law of inertia. Newton’s first law states that if a body moving at a constant speed in a straight line, it will remain at rest or keep moving in a straight line at constant speed unless it is acted upon by a force.

We know that bullets drop because of gravity, and the speed changes because of wind resistance. Wind will affect the straight line but that is random and chaotic at best and impossible to duplicate shot after shot, group after group.

Until little thruster jets are built into bullets I would have to call convergence theory to be fertilizer produced from the digestive tract of a male bovine

Who exactly said anything about convergence theory except you? What is this convergence theory you speak of? Does anything in your response has anything to do with the original subject/question? Convergence definition implies 2 or more seperate things coming together. Are you suggesting 2 differing bullets converging?

In order to assist, here is a link to the definition of convergence.
https://www.merriam-webster.com/dictionary/convergence

hounddawg · August 2, 2022, 01:22 PM

Quote:

Originally Posted by stagpanther

This subject came up here a few years ago--specifically, do some bullets show a propensity to actually get better accuracy past the "standard" test range of 100yds?

@ Zeke- The way I interpreted this statement in the OP is that a load that produces a 1 MOA group at 100 would get .5 MOA at 200 which is how I define better accuracy. How do you interpret it ?

Metal god · August 2, 2022, 02:10 PM

Quote:

The way I interpreted this statement in the OP is that a load that produces a 1 MOA group at 100 would get .5 MOA at 200 which is how I define better accuracy. How do you interpret it ?

Me too .

Quote:

Again, no one except you said the group was smaller at 300 yds. What was said was accuracy was better, and smaller moa. To simply explain this, a 1 moa group at 100 yds is 1 inch. A .75 moa group at 300 yds is 2.25 in. While the 2.25 in group at 300 yards is physically larger, it represents better accuracy.

1moa to .75moa is absolutely a smaller group regardless of distance . A 1moa group can't become a .75 moa group with out the trajectory changing correct ?

Which is why I said from the start the question needs to be better defined , It's the very reason I used MOA and not inches . We all know what MOA is and how it's defined . Could I have been more clear , maybe but figured we were all talking in good faith .

Quote:

Originally Posted by Me and very first sentence in my first post

I think the question needs to be better defined for me to understand

zeke · August 2, 2022, 02:21 PM

Well at least you guys quit digging, and appear to be starting to climb out of it (hole).

yes i am describing better accuracy as smaller moa at longer distance (see answer in post #19). Even if the group at 100 yds is smaller.

Although technically what we are calling better accuracy is really greater precision?

Metal god · August 2, 2022, 02:26 PM

Not sure if you saw my EDIT above

zeke · August 2, 2022, 03:36 PM

Quote:

Originally Posted by Metal god

Not sure if you saw my EDIT above

"1moa to .75moa is absolutely a smaller group regardless of distance"

A 1 moa group at 100 yds is 1 inch. A .75 moa group at 300 yds is 2.25 inches. A 2.25 inch circle is a larger circle than a 1 in circle in anybody's book, but yours.

A inch is a physical size measurement. 1 in at 100, 200 or 300 yds is 1 inch

MOA is an angular measurement that increases in size at increasing distances.

Minute of Angle

A Minute of Angle (MOA) is an angular measurement. A MOA is 1/60th of a degree. 1 MOA spreads about 1″ per 100 yards. ( actually 1.047″) 1 MOA is a different size at different distances, 8″ at 800 yards is still just 1 MOA.

A wise old redneck ditch digger once said, the longer you dig, the deeper you get.

August 1, 2022, 09:56 AM	#2
Bart B. Senior Member Join Date: February 15, 2009 Posts: 8,927	If slower bullets leave at higher angles to the line of sight than faster ones, their trajectories will cross trajectories of faster bullets at some point down range. Long, skinny barrels wiggle more in the vertical plane than short, fat ones Weights (tuners) on the barrel at the muzzle move back and forth change the bore axis vibration frequency so slower ones do that. .22 rimfire match rifles often have them and have different settings for each range of 50 feet, 50 and 100 yards and meters. Highpower match rifles have settings for several ranges to 1000 yards. Check out these websites..... https://www.varmintal.com/apres.htm http://www.geoffrey-kolbe.com/articl...vibrations.htm Sierra used to test at 100 yards but changed to 200 yards several years ago. Their match bullets have to shoot under half an inch extreme spread. Last edited by Bart B.; August 1, 2022 at 03:56 PM.

August 1, 2022, 01:20 PM	#3
stagpanther Senior Member Join Date: March 2, 2014 Posts: 11,792	Thanks for that Bart. If I understand the information in the link correctly, it more or less says that there is an optimal moment for a bullet to leave a barrel at a certain velocity relative to the degree of the barrel's whip to attain best consistency? I take that to mean this really has nothing to do with any notion of the projectile's spin causing the bullet to destabilize and then subsequently "restabilizing" itself? __________________ "Everyone speaks gun."--Robert O'Neill *I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk!*

August 1, 2022, 01:29 PM	#4
Metal god Senior Member Join Date: April 10, 2012 Location: San Diego CA Posts: 6,876	I think the question needs to be better defined for me to understand . I remember that thread and could not except that the bullet changes direction between muzzle and 200yds . What I was hearing in that thread for example but was not actually said this way . This assumes bore axis and POA are dead on when bullet leaves muzzle . A bullet leaves the muzzle at a 2* off center of POA and bore axis and at some point between muzzle and 200yds that trajectory changes from 2* to 1.5 or 1* off axis . Ok a body in motion stays in motion until …. So what is being said is the spin on the bullet is the “other” force acting upon the bullets trajectory changing it’s trajectory ?? Even if I agreed which does in fact seem plausible . Wouldn’t that mean that action could only go in one direction . So if the spin of a bullet causes it to pull to the left and you shoot a tad right it “may” pull it back to the left . What happens when you shoot to the left a tad to start with ? Are we now saying there is some force while the bullet is in flight to not only act against the initial straight line trajectory but also act against the second force of spin drift pushing it to the left as well ? __________________ If Jesus had a gun , he'd probably still be alive ! I almost always write my posts regardless of content in a jovial manor and intent . If that's not how you took it , please try again .

August 1, 2022, 04:10 PM	#7
jmr40 Senior Member Join Date: June 15, 2008 Location: Georgia Posts: 10,809	If I understand correctly the question is something along the lines of; Is it possible to have a rifle that will shoot at best 1.5 MOA at 100 yards, but then shoot 1 MOA at 200 or 300 yards? That does not mean the rifle will shoot smaller groups at 200 or 300 than at 100. 1.5 MOA at 100 yards is roughly 1.5". One MOA at 200 would be 2" and 1 MOA at 300 would be 3". In rare cases I have observed this. But I've never seen a rifle that would consistently shoot smaller groups at longer ranges than shorter ranges. I don't see how that would be possible. Virtually all of the time accuracy at all ranges is pretty predictable based on 100-yard accuracy. At least up to a point. MOST rifles/loads that are 1 MOA at 100 will be 1 MOA at 200-300 as well. Once you get much past 300 yards things usually open up. A rifle that shoots 1 MOA at ranges 300 or less may or may not be that good at 500 yards. Whether or not this is real, or just a case of shooters aiming more precisely at long range is hotly debated. The last that I read about Litz was that he did not believe this phenomenon was real. But he may have changed his mind. All I can say is that I've observed this a few times and don't know why. Maybe it was just a fluke, it doesn't happen often. But the times I observed it, it appeared to be with an individual rifle. Cartridge, load, or caliber didn't seem to matter. __________________ "If you're still doing things the same way you were doing them 10 years ago, you're doing it wrong" Winston Churchill

August 1, 2022, 06:41 PM	#11
Metal god Senior Member Join Date: April 10, 2012 Location: San Diego CA Posts: 6,876	I was wondering how Bart enjoyed his free flight and hotel when he went to prove this can happen . __________________ If Jesus had a gun , he'd probably still be alive ! I almost always write my posts regardless of content in a jovial manor and intent . If that's not how you took it , please try again .

August 1, 2022, 04:18 AM	#1
stagpanther Senior Member Join Date: March 2, 2014 Posts: 11,792	spin stabilization of projectile--yes or no? This subject came up here a few years ago--specifically, do some bullets show a propensity to actually get better accuracy past the "standard" test range of 100yds? I've read in Litz's books that he believes this does happen in some cases and I think that was the argument being made at the time here. At the time, I scoffed at the idea thinking it was an impossibility. I've heard the idea of gases exited at the muzzle cause a disrupt--which I find plausible--it was the "centrifugal self-correction" part I had trouble with. Well, some time has gone by and I've shot a lot of bigger magnum type cartriges--and--spoiled as we are as shooters--a whole new breed of ultra-high BC bullets have come out as well for these bigger cartridges. I've actually come around to the idea that some cartridges do in fact get better results when tested at longer range than 100 yds--like my 338LM, 7mmSTW, etc. It's gotten to the point where I don't bother developing loads for the big ones under 200 to 300 yds. Your experience/ideas? __________________ "Everyone speaks gun."--Robert O'Neill *I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk!*

August 1, 2022, 03:23 PM	#5
Jim Watson Senior Member Join Date: October 25, 2001 Location: Alabama Posts: 18,544	What Bert describes is what I have seen called "compensation." The Lee Enfield was particularly well known at Bisley for twanging its barrel so as to bring bullets of different velocity to the same elevation at range. I recall mention of it all coming together at 600 yards. This is entirely different from the legend of bullets "going to sleep" downrange and yawing less which somehow automatically causes them to converge on the center. Nope.

August 1, 2022, 04:32 PM	#8
Jim Watson Senior Member Join Date: October 25, 2001 Location: Alabama Posts: 18,544	I recall the Brian Litz challenge. Your rifle, your ammo, his range. Shoot through a thin paper target at 100 yards, in line with another target at 300 yards. Can you make the SAME BULLETS land closer or even relatively closer at the longer target? I once read posts by a guy who had set that up with an Oehler Acoustic Target. Never did get convergence.

August 1, 2022, 10:32 PM	#13
Metal god Senior Member Join Date: April 10, 2012 Location: San Diego CA Posts: 6,876	If a rifles best group at 100yds is 2moa and yet at 300yds it can shoot 1/2 moa . The bullet “is” changing direction between 100 & 300yds . Furthermore my point that “if” the bullet did yaw or whatever it would only be in one direction. As my example pointed out all shots to the right of POA may come back left a bit but shots left of POA would go further left do to the spin/yaw . Meaning you’re still not going to shoot better groups if all shots at zeroed on POA , at least not consistently __________________ If Jesus had a gun , he'd probably still be alive ! I almost always write my posts regardless of content in a jovial manor and intent . If that's not how you took it , please try again . Last edited by Metal god; August 1, 2022 at 10:38 PM.

August 2, 2022, 02:46 AM	#14
stagpanther Senior Member Join Date: March 2, 2014 Posts: 11,792	Well, I do have deteriorating eyesight and it does make sense that perhaps I'm just concentrating better at the longer distance than 100 yds. __________________ "Everyone speaks gun."--Robert O'Neill *I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk!*

August 2, 2022, 07:53 AM	#16
zeke Senior Member Join Date: November 17, 1999 Location: NW Wi Posts: 1,671	For those unfamiliar with projectile yaw, consider googling army testing of projectile yaw. They have been studying "yaw" for decades, mostly for maximizing armor penetration in artillery /rifle rounds.

August 2, 2022, 10:26 AM	#17
Metal god Senior Member Join Date: April 10, 2012 Location: San Diego CA Posts: 6,876	I know what yaw is and that is/was not my point . Even if the bullet is crazy unstable/yawing out to 100yds then settles down and flys perfectly straight from there . The group at 300 yards is not going to be smaller then the best groups at 100 , is all my point is . I don’t care if the bullet is tumbling out to 100yds then Stabilizes and flies true after that . The group is not going to be better at 300 then the best at 100 unless the bullet changes it’s trajectory/direction between 100 & 300yds . If the bullet can shoot a smaller group at 300 then it does at 100 . It would be reasonable to conclude the groups will continue to get smaller the further the bullet travels ? Are you saying the yaw effect has a constant and reliable effect that reduces group size the further out the bullet travels. __________________ If Jesus had a gun , he'd probably still be alive ! I almost always write my posts regardless of content in a jovial manor and intent . If that's not how you took it , please try again . Last edited by Metal god; August 2, 2022 at 10:32 AM.

August 2, 2022, 10:47 AM	#18
hounddawg Senior Member Join Date: March 1, 2009 Posts: 4,232	Newton’s first law is the the law of inertia. Newton’s first law states that if a body moving at a constant speed in a straight line, it will remain at rest or keep moving in a straight line at constant speed unless it is acted upon by a force. We know that bullets drop because of gravity, and the speed changes because of wind resistance. Wind will affect the straight line but that is random and chaotic at best and impossible to duplicate shot after shot, group after group. Until little thruster jets are built into bullets I would have to call convergence theory to be fertilizer produced from the digestive tract of a male bovine __________________ “How do I get to the next level?” Well, you get to the next level by being the first one on the range and the last one to leave.” – Jerry Miculek

August 2, 2022, 02:21 PM	#23
zeke Senior Member Join Date: November 17, 1999 Location: NW Wi Posts: 1,671	Well at least you guys quit digging, and appear to be starting to climb out of it (hole). yes i am describing better accuracy as smaller moa at longer distance (see answer in post #19). Even if the group at 100 yds is smaller. Although technically what we are calling better accuracy is really greater precision?

August 2, 2022, 02:26 PM	#24
Metal god Senior Member Join Date: April 10, 2012 Location: San Diego CA Posts: 6,876	Not sure if you saw my EDIT above __________________ If Jesus had a gun , he'd probably still be alive ! I almost always write my posts regardless of content in a jovial manor and intent . If that's not how you took it , please try again .