# Video of bullet yaw 180 gr Berger .284



## RB II (Feb 26, 2009)

Very cool/informative video of the track/spin/wobble of a projectile. Specifically the 180 gr Berger in .284. Basically about 150 yds it stabilizes and the group just gets tighter the further down range it travels. The BC of these bullets is approx .652 (I didn't look it up just now).


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## ReelWork (May 21, 2004)

Really wild and interesting to see how it just starts zeroing in stabilizing at about 80 yards and just gets tighter.


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## spurgersalty (Jun 29, 2010)

Jammer had mentioned something to this effect previously(moa going to sub moa at longer distances).
It would seem that some adjustment or another could be made to correct short range "accuracy" or bullet flight though. Maybe seating depth? Muzzle crown? I didn't notice any specs mentioned such as barrel make, length, crown or the likes.
BTW, I challenge you to a 100 yard match


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## THE JAMMER (Aug 1, 2005)

This is very interesting, and I am still pondering it. What it means. What could be done to affect it. It certainly explains the disparity between accuracy of the same load at different distances. In black powder cartridge, it is not uncommon at all to have much better groups at farther distances.

I just want to know what affects it. What makes it happen. There is smoke coming out of my ears thinking about this.


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## Ernest (May 21, 2004)

Miller Stability Formula. Look at the SG in that video. 

It's the shape of the bullet - length/weight, velocity, and twist. 

Some Palma bullets out of slow twist weapons purportedly don't go to sleep for 300+ yards. 

Berger is long for its weight. A flat based bullet of the same weight with a shorter length will stabilize quicker. Hence the stubbies the benchrest boys use for the short distances.


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## spurgersalty (Jun 29, 2010)

THE JAMMER said:


> This is very interesting, and I am still pondering it. What it means. What could be done to affect it. It certainly explains the disparity between accuracy of the same load at different distances. In black powder cartridge, it is not uncommon at all to have much better groups at farther distances.
> 
> I just want to know what affects it. What makes it happen. There is smoke coming out of my ears thinking about this.


Myself. It's as intriguing as "velocity nodes". 
I recently began a workup on my 6.5 mag with RL22 and SMK's. From 49 to 50.5 grains the 50 grain was the only one that went sub-moa. The second load (49.5) only put 2 holes on paper. 
The 50 grain load(sub-moa) was just a bit better than the 50.5 load. I have 2.5 grains to go until max(quickloads calculated max), and am wondering if it will be wasted time and money to try it. Ive heard and read of a 2 velocity "node" phenomenon, and, I guess I'll test the theory and continue up. But still, :scratching my head:
Seating depths remained constistent through testing and I used a "round robin" method to decrease any potential changes/lvariations to the groups.


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## WesinTX (Jan 23, 2011)

That's why a man told me " don't pay attention 100yrd groups, shoot all your loads at 200yrds" when I first started hand loading.


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## RB II (Feb 26, 2009)

spurgersalty said:


> Jammer had mentioned something to this effect previously(moa going to sub moa at longer distances).
> It would seem that some adjustment or another could be made to correct short range "accuracy" or bullet flight though. Maybe seating depth? Muzzle crown? I didn't notice any specs mentioned such as barrel make, length, crown or the likes.
> BTW, I challenge you to a 100 yard match


One of the guys who loads this bullet swears that OAL/seating depth is CRITICAL to 100 yd groups with this bullet. He get ragged one holes with them. Of course that guy loads a lot AND can shoot. Seriously, he loads up close to max and then just plays with the OAL in small increments until he finds the sweet spot.

That's a deal on the 100 yds, but I won't be shooting this rifle. Got an OLD Fabrique Nationale in .270 that is literally a one holer at 100 yds with factory 130 gr loads. Wouldn't be a fair match.:slimer:


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## spurgersalty (Jun 29, 2010)

I fully intend (after I get firmly situated back home) to set up a 2Cool shoot out. I have 4 "for sures" so far.
Think about it a bit and we'll "settle" it:cheers:


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## RB II (Feb 26, 2009)

spurgersalty said:


> I fully intend (after I get firmly situated back home) to set up a 2Cool shoot out. I have 4 "for sures" so far.
> Think about it a bit and we'll "settle" it:cheers:


I am in. I love to shoot. Got a couple of rifles that might be able to hang.


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## spurgersalty (Jun 29, 2010)

Still, something baffles me about that vid. There's to be something to correct or adjust for in my opinion..
Maybe I need to research other bullets designed for "short term" stability(like exes).


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## RB II (Feb 26, 2009)

I think that performance is different for each bullet, not that something is wrong. just that each has different characteristics. Some "go to sleep" faster than others, some never reach that total sleep/stability that this one appears to for max long range accuracy. The BC of this particular bullet speaks to its ability to spin truer the further it travels. I am not really into the "physics side of shooting, rather just give me the performance and I am good.


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## spurgersalty (Jun 29, 2010)

I'm a "got's to know" kind of guy. 
Plan on researching and studying a bit.


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## RB II (Feb 26, 2009)

spurgersalty said:


> I'm a "got's to know" kind of guy.
> Plan on researching and studying a bit.


Cool, when you figure it out..............let me know!!!!!! Lol. I just close my eyes and squeeeeeeeeeeze that trigger.

Says I gotta spread it around before I can give those "gots to know" greenies. Lol


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## dwilliams35 (Oct 8, 2006)

I'm wondering if just the transition between the barrel and the air, the disrupted air at the muzzle, plus the sudden shift between propellant and drag is disruptive enough to get it out of whack, then as time goes on the spin and travel through relatively "cleaner" air smooths everything out?


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## spurgersalty (Jun 29, 2010)

dwilliams35 said:


> I'm wondering if just the transition between the barrel and the air, the disrupted air at the muzzle, plus the sudden shift between propellant and drag is disruptive enough to get it out of whack, then as time goes on the spin and travel through relatively "cleaner" air smooths everything out?


That was a thought I had. A target "crowned" muzzle versus a "factory" muzzle.


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## THE JAMMER (Aug 1, 2005)

Giddy up!!


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## CHARLIE (Jun 2, 2004)

Well being of the old timey type of guy I am still wondering how "they" whoever they are came up with this so called video of the bullet. I really think it is all theory and not real time. Let me see if I can splain this (my opinion). Tell me how the group can get tighter and tighter further down range when you cannot determine where the bullet may be during its track down range when it begins to stabilize. It may be off track an inch or two when it "straightens up"

If in fact it does stabilize its because of the spin or twist rate becoming optimum for that bullet as it slows down. HA


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## THE JAMMER (Aug 1, 2005)

dwilliams35 said:


> I'm wondering if just the transition between the barrel and the air, the disrupted air at the muzzle, plus the sudden shift between propellant and drag is disruptive enough to get it out of whack, then as time goes on the spin and travel through relatively "cleaner" air smooths everything out?


I can possibly see that. Much like an arrow starts out from the bow all bent and crooked, and then the fletching straightens it out.

VERRRY EENTERESTING.


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## B-Money (May 2, 2005)

my bullets don't make blue squiggly lines when they fly. My bullets make cammo squiggly lines. That's why you can't see them.


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## kanga69 (Mar 17, 2011)

No direct knowledge but I think it has a lot to do with the weight of the bullet in combination to the barrel harmonics that makes a bullet stabilize quicker. i.e. in theory the heavier the barrel, generally speaking, the more accurate the gun. As i write this, I find possible holes in this theory, just curious.


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## Bottomsup (Jul 12, 2006)

Check out tedsholdover.com and watch the video about spiraling pellets he films in slow motion. The airgun world has tried everything the figure out why some shots will spiral and others dont.


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## Law Dog (Jul 27, 2010)

Very interesting...thanks for sharing!


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## dwilliams35 (Oct 8, 2006)

kanga69 said:


> No direct knowledge but I think it has a lot to do with the weight of the bullet in combination to the barrel harmonics that makes a bullet stabilize quicker. i.e. in theory the heavier the barrel, generally speaking, the more accurate the gun. As i write this, I find possible holes in this theory, just curious.


 I think it's pretty much a given that the correct harmonics may send a bullet out "straighter" to begin with, but once it leaves the barrel, it's on its own: barrel harmonics can have no effect on what happens AFTER it leaves the muzzle, and can't have any effect on how quickly it stabilizes: only air, rpm, and internal balance/mass distribution is in play there.


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## Longshot270 (Aug 5, 2011)

dwilliams35 said:


> I'm wondering if just the transition between the barrel and the air, the disrupted air at the muzzle, plus the sudden shift between propellant and drag is disruptive enough to get it out of whack, then as time goes on the spin and travel through relatively "cleaner" air smooths everything out?


I do know there is something to that. A friend of mine is a gunsmith and was working on some muzzle breaks for a while. He showed me the before and after targets of one of his guns and within 100 yds, they looked close enough to be confused. But after that, the muzzle break cleaned up much faster than the stock barrel. Something about the pressures and such. I'm a rather techy guy but his explanation didn't help me much. His job requires expertise on guns, I just shoot them for fun. I said to just set the rifle up to sling them out and I'll hold it steady so it can.


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