Bullets accurate at 600yd but not 100yd?

[ARCHIVED THREAD] - Bullets accurate at 600yd but not 100yd? (Page 1 of 9)

Posted: 1/8/2014 11:15:00 AM EDT

I've heard this before a few times. Any truth to it?

Supposedly some bullets (talking 223/308/etc) will be 1.5 moa at 100 but sub at 600. What is the physics involved in this. Sounds like a old wives tale at first.
So for powder load development should someone test at whatever distance they plan to shoot at?

Posted: 1/8/2014 11:15:58 AM EDT

[#1]

My brain doesn't want to accept that as truth.

Posted: 1/8/2014 11:17:22 AM EDT

[#2]

That is totally possible, depending on at what distance you have the gun zeroed at!

Posted: 1/8/2014 11:19:50 AM EDT

[#3]

Its BS

Posted: 1/8/2014 11:20:00 AM EDT

[#4]

I've heard that boat tailed bullets need some distance to stabilize after exiting the muzzle.

Posted: 1/8/2014 11:20:42 AM EDT

[#5]

I'm not buying it. Any errors caused by assymetries in bullet profile or weight should tend to get worse over distance. A bullet has no knowledge of where the shooter intended it to go.

Posted: 1/8/2014 11:20:54 AM EDT

[#6]

Have heard of this myself, though I think I slept through that chapter of my ballistics book. "Takes 'em time to settle down" I've heard it put.

Posted: 1/8/2014 11:22:23 AM EDT

[#7]

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That is totally possible, depending on at what distance you have the gun zeroed at!

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no because you might not hit the bullseye but the groups would have to be sub moa at all points.

well unless you had a sewer pipe and the bullets just happened to bounce off of shit and all hit together.

Posted: 1/8/2014 11:25:13 AM EDT

[#8]

Palma bullets..

or adjust the CG back a bit. IIRC..

Posted: 1/8/2014 11:26:09 AM EDT

[#9]

That is impossibru.

Posted: 1/8/2014 11:26:25 AM EDT

[#10]

I've not heard of that with modern high velocity bullets, but it most certainly is true for the 530 grain bullets that I cast for my 45-90 BPCR.
Why? I have ideas but no proof, but they have a larger MOA grouping at 100yds than they do at 300yds.

Posted: 1/8/2014 11:26:36 AM EDT

[#11]

I think it is because of magnets.

Posted: 1/8/2014 11:27:18 AM EDT

[#12]

It has been known in many circles for years.

Some bullets take time to "Go to Sleep".

Ask any ranking High Power shooter.

Posted: 1/8/2014 11:27:44 AM EDT

[#13]

Often based upon the experience of British military shooters and their .303 Enfields. They swore that the bullets "settled down" at longer ranges and were more accurate at longer ranges than at shorter ranges.

Many American shooters laughed at this idea, but tests done seemed to indicate that the Brits were right after all.

Posted: 1/8/2014 11:27:46 AM EDT

[#14]

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no because you might not hit the bullseye but the groups would have to be sub moa at all points.

well unless you had a sewer pipe and the bullets just happened to bounce off of shit and all hit together.

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Quoted:

Quoted:
That is totally possible, depending on at what distance you have the gun zeroed at!

no because you might not hit the bullseye but the groups would have to be sub moa at all points.

well unless you had a sewer pipe and the bullets just happened to bounce off of shit and all hit together.

Good point, i didnt think it through all the way.

Posted: 1/8/2014 11:28:21 AM EDT

[#15]

i don't know one way or the other but have guys ever seen arrows fired from a bow? They seem to be all wobbly when they are first fired.

Posted: 1/8/2014 11:29:32 AM EDT

[#16]

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Quoted:
I've not heard of that with modern high velocity bullets, but it most certainly is true for the 530 grain bullets that I cast for my 45-90 BPCR.
Why? I have ideas but no proof, but they have a larger MOA grouping at 100yds than they do at 300yds.

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Could it be you're aiming at a better target at 300?

Posted: 1/8/2014 11:29:50 AM EDT

[#17]

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Quoted:
It has been known in many circles for years.

Some bullets take time to "Go to Sleep".

Ask any ranking High Power shooter.

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shape, length, CG and boat tail can do all kids of weird shit at long ranges.

Posted: 1/8/2014 11:31:14 AM EDT

[#18]

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Its BS

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Posted: 1/8/2014 11:32:01 AM EDT

[#19]

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shape, length, CG and boat tail can do all kids of weird shit at long ranges.

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Quoted:

Quoted:

It has been known in many circles for years.

Some bullets take time to "Go to Sleep".

Ask any ranking High Power shooter.

shape, length, CG and boat tail can do all kids of weird shit at long ranges.

Yep.

Here is another brain twister for the dirt shooters:

Flat base bullets tend to be much more accurate out to 300ish yards than their boat-tail cousins.

Posted: 1/8/2014 11:32:17 AM EDT

[#20]

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I've heard that boat tailed bullets need some distance to stabilize after exiting the muzzle.

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Same here.

Posted: 1/8/2014 11:33:26 AM EDT

[#21]

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Quoted:

Could it be you're aiming at a better target at 300?

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Quoted:

Quoted:
I've not heard of that with modern high velocity bullets, but it most certainly is true for the 530 grain bullets that I cast for my 45-90 BPCR.
Why? I have ideas but no proof, but they have a larger MOA grouping at 100yds than they do at 300yds.

Could it be you're aiming at a better target at 300?

I don't think so.
The phenomenon is very common amongst BPCR shooters.

Posted: 1/8/2014 11:35:39 AM EDT

[#22]

Quote History

Quoted:

Yep.

Here is another brain twister for the dirt shooters:

Flat base bullets tend to be much more accurate out to 300ish yards than their boat-tail cousins.

View Quote View All Quotes

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Quote History

Quoted:

Quoted:
It has been known in many circles for years.

Some bullets take time to "Go to Sleep".

Ask any ranking High Power shooter.

shape, length, CG and boat tail can do all kids of weird shit at long ranges.

Yep.

Here is another brain twister for the dirt shooters:

Flat base bullets tend to be much more accurate out to 300ish yards than their boat-tail cousins.

OMG you HAVE to try a cupped based one! Killer driving band!
Yup the boat tail only make a difference at sub sonic speeds. Less disturbance behind the slow bullet.

Posted: 1/8/2014 11:35:52 AM EDT

[#23]

I think Berger or Sierra had a video illustrating the effect. Basically, the projectile was making small circular rotations that tightened over time.

Posted: 1/8/2014 11:36:01 AM EDT

[#24]

It's an absolute fact that is demonstrable, has been demonstrated before, observed, documented, researched and repeated.

Ziarifleman will be along shortly, I'm sure.

I'll not go into the physics of it, because it's been done here before.

Don't believe me, get a precision rifle, load several different sets of rounds using different bullets and powders. Shoot at 100 and then a further distance (at least 300).

Not always but fairly often you will see MOA decrease at distance.

Posted: 1/8/2014 11:36:03 AM EDT

[#25]

Curving bullets? They start off "off" and and find their way back "on?"

News to me. I have very little experience in any kind of long range shooting, so I won't argue the point, but I would love for someone to explain the physics behind that.

Posted: 1/8/2014 11:37:24 AM EDT

[#26]

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Curving bullets? They start off "off" and and find their way back "on?"

News to me. I have very little experience in any kind of long range shooting, so I won't argue the point, but I would love for someone to explain the physics behind that.

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The theory is that the wobble of the bullet as it exits the bore settles down at distance (time).

Posted: 1/8/2014 11:38:30 AM EDT

[#27]

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i don't know one way or the other but have guys ever seen arrows fired from a bow? They seem to be all wobbly when they are first fired.

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Different principle. Arrows are "squashed" and bent as they leave the bow.

Posted: 1/8/2014 11:38:52 AM EDT

[#28]

My mind is not handling this.

Posted: 1/8/2014 11:39:14 AM EDT

[#29]

Also heard something like that. Boat tails grp better at longer ranges than Flat base bullets.

Posted: 1/8/2014 11:39:27 AM EDT

[#30]

I gather the thought is that the bullet path can be a bit of a spiral that tightens as the spinning of the bullet stabilizes things. Its one of those things that are really hard to measure any true affect on accuracy.

Posted: 1/8/2014 11:40:34 AM EDT

[#31]

Quote History

Quoted:
OMG you HAVE to try a cupped based one! Killer driving band!

Yup the boat tail only make a difference at sub sonic speeds. Less disturbance behind the slow bullet.

View Quote View All Quotes

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Quote History

Quoted:

Quoted:

It has been known in many circles for years.

Some bullets take time to "Go to Sleep".

Ask any ranking High Power shooter.

shape, length, CG and boat tail can do all kids of weird shit at long ranges.

Yep.

Here is another brain twister for the dirt shooters:

Flat base bullets tend to be much more accurate out to 300ish yards than their boat-tail cousins.

OMG you HAVE to try a cupped based one! Killer driving band!

Yup the boat tail only make a difference at sub sonic speeds. Less disturbance behind the slow bullet.

Like a Miniet Ball, or a .22lr.

Posted: 1/8/2014 11:40:51 AM EDT

[#32]

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My mind is not handling this.

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Then whatever you do, don't go read the "bullet stabilization down range" thread on the shooter's forum. It'll break yo head.

Posted: 1/8/2014 11:41:06 AM EDT

[#33]

Doesn't follow physics. MOA is MOA is MOA.

Posted: 1/8/2014 11:41:45 AM EDT

[#34]

Posted: 1/8/2014 11:41:50 AM EDT

[#35]

Are you fucking with this 13er or are there links for this subject?

Posted: 1/8/2014 11:42:07 AM EDT

[#36]

I have heard "epicyclic swerve" blamed for it. Basically that when the bullet leaves the barrel, there is a corkscrew effect on it, where the rear end wobbles, as the velocity bleeds off, the bullet spins "tighter".

I am not sure how much the effect can really make a difference.

When people claimed this happened and had "proof", I always just assumed that the distance to the target changed their sight picture for the better.

Posted: 1/8/2014 11:42:11 AM EDT

[#37]

Quote History

Quoted:
Its BS

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Posted: 1/8/2014 11:42:26 AM EDT

[#38]

True Mark Larue posted a great link a few years ago. bullets settle I'll try to find it later unless someone beats me to it. On my phone pia

Posted: 1/8/2014 11:42:31 AM EDT

[#39]

Quote History

Quoted:
I've heard that boat tailed bullets need some distance to stabilize after exiting the muzzle.

View Quote

Which would affect accuracy at every distance.

Posted: 1/8/2014 11:42:41 AM EDT

[#40]

I had a .264 WinMag that you couldn't hit shit with inside of 200 yards. But I'd be damned if you couldn't hit half dollars at 500 yards with it.

Never could figure it out so I sold it.

Posted: 1/8/2014 11:42:54 AM EDT

[#41]

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Doesn't follow physics. MOA is MOA is MOA.

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Lol.

Only when MOA is MOA.

Many shooters with a great deal of knowledge on the subject (and the skill to demonstrate it) can show you that certain bullets will go to sleep at range, and group better than at cloase range.

Posted: 1/8/2014 11:43:01 AM EDT

[#42]

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Like a Miniet Ball, or a .22lr.

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Like a 22lr just a slight cup. I got some great groups from them.

Posted: 1/8/2014 11:43:43 AM EDT

[#43]

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i don't know one way or the other but have guys ever seen arrows fired from a bow? They seem to be all wobbly when they are first fired.

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That is because of the elasticity of the arrow shaft. When it first leaves the string, the back is trying to move faster than the head.

Posted: 1/8/2014 11:43:47 AM EDT

[#44]

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Doesn't follow physics. MOA is MOA is MOA.

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The bullet hasn't properly stabilized, and is wobbling at short distances. At a longer range, it will "settle in" and fly true.

It doesn't make much sense, but what I've heard is it's a common phenomenon when pushing long for caliber bullets.

Posted: 1/8/2014 11:43:51 AM EDT

[#45]

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Quoted:
Doesn't follow physics. MOA is MOA is MOA.

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Assuming you are shooting laser beams....

Posted: 1/8/2014 11:43:59 AM EDT

[#46]

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Which would affect accuracy at every distance.

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Quoted:

Quoted:

I've heard that boat tailed bullets need some distance to stabilize after exiting the muzzle.

Which would affect accuracy at every distance.

Nope

Certain bullets calm down, and go to sleep at distance.

THis has already been covered by many posters in this thread.

Posted: 1/8/2014 11:44:11 AM EDT

[#47]

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Are you fucking with this 13er or are there links for this subject?

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there are BOOKS on this shit.. LOTS o books..

Posted: 1/8/2014 11:44:40 AM EDT

[#48]

It's called the zen effect and has nothing to do with physics, more common with iron sights and low powered optics. I once shot a coke bottle at 175 yards with a ruger mark II, one shot one kill zen man, zen.

Posted: 1/8/2014 11:44:59 AM EDT

[#49]

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I gather the thought is that the bullet path can be a bit of a spiral that tightens as the spinning of the bullet stabilizes things. Its one of those things that are really hard to measure any true affect on accuracy.

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I've measured it plenty of times. My Winchester stealth in a McMillan stock, shooting 168 SMK on top of (iirc) 44gr of Varget will group at about .75" @ 100 yards. They shoot into under 1' @200 yards.