calling all LONG RANGE SHOOTING experts!

Ditto...
Eye opening article.

Really makes me re-think optimal barrel lengths.

Seems that a hunting rifle- for most shorter range engagement, up to a few hundred yards, would be more accurate with a 16" barrel (or even shorter, if the SBR stamp is not a factor)- in as heavy a contour as the shooter wishes to carry.

You certainly do not need the additional velocity of a longer barrel for this application- so rather than a 24" barrel weighing "X" pounds, a 16" barrel weighing "X" pounds would be more accurate. Not only more accurate, but much easier to carry due to it's reduced length.

Or, am I mis-reading the physics D.L. presented in the article?
 
For those thinking long, whippy barrels won't shoot accurate at long range, buddy up to folks shooting the best scores in Palma matches. You'll learn that when they test those barrels, the best of them will shoot under 1/2 MOA at 800 yards and a bit bigger at 1000. Same as short, stiff rail gun barrels do in 1000 yard benchrest matches.

Don't forget folks; if the barrel whips the same for each shot, it doesn't matter how much they whip. Best accuracy will happen. And all barrels whip the same amount and direction for each shot with a given load from a well built rifle. Some whip more and other less. And they're more repeatable from shot to shot than the powder charge and primer. Their metalurgy and shape doesn't change from shot to shot.
 
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I don't know that the Chris Long's barrel harmonics theories have ever been "proved" (technically impossible, can only be DISproved) but the folks at RSI have incorporated his theory into their software. If your bullet exits when they say it shouldn't and your accuracy stinks but your accuracy improves when the bullet exits when they say it should...

Is that "proof" enough?

http://www.shootingsoftware.com/barrel.htm
 
If your bullet exits when they say it shouldn't and your accuracy stinks but your accuracy improves when the bullet exits when they say it should...
Click to expand...

How would you even know? You can calculate, and play with the numbers in quickload to try and match the predicted barrel time to what the math says is the right spot, but without expensive measuring equipment and million frame per second high speed video you are at best guessing.

Oh, and guess what? You ran out of powder, and the new jug you bought is a different lot. Start over......

From a practical aspect, all these calculations are interesting, but they are about as useful as the male nipple.
 
You know if you have RSI Pressure Trace.
Click to expand...

I had never even heard of it until I was corresponding with a guy that uses it for developing "oddball" loads- like 6mm out of a Mosin Nagant...
Pretty amazing technology, and not "unaffordable" for the really serious handloader that likes to play...
 
but they are about as useful as the male nipple.
Click to expand...

Useful no, but needed yes. I am talking about the nipple of course, not calculating the barrel vibration. If the male were to not have nipples, there is a possibility that the female wouldn't be passed the gene either. Thus rendering those wonderful things on her chest, into strange water bags.


Yes, I am a member of T*tts anonymous.
 
Emcon5 mentions:
You can calculate, and play with the numbers in quickload to try and match the predicted barrel time to what the math says is the right spot, but without expensive measuring equipment and million frame per second high speed video you are at best guessing.
Click to expand...
That's right. Some decades ago at a USA arsenal, an M1903 Springfield was clamped in a machine rest with a sensor on its muzzle. Bullets were fired through a spark gap generator that indicated when the bullet left relative to the bore position. They left close to the top of the first upswing as the barrel whipped; slower ones at a higher angle, faster ones at a lower angle. The Brits did the same thing around that same time and got the same results with their SMLE's except the vertical swing of the barrel covered a greater arc.

'Twould be easy to do these days. All that's needed is accelerometers attached to the barrel right behind the muzzle. They would measure the barrel movement vs time. Then syncronize a high speed video camera (10 to 50 thousand frames per second would be enough) to the accelerometer with a computer and start shooting bullets. Oh yes, gotta have a target down range to correllate bullet holes to the shots fired. I don't know of anybody that's done this.

Regarding Chris Longs web site with the following picture:

sinewave.gif


The places where the arrow points are not harmonic nodes. They are fundamental nodes that are where the barrel doesn't whip at all. Two of them typically exist on a fired barrel. Harmonic nodes are much closer together 'cause the frequency they occur at are multiples of the fundamental frequency..2x is the second harmonic, 3x is the third and so on. There's three harmonic nodes for every fundamental one. More important, its the fundamental ones that cause the greatest amount of barrel whip; harmonic ones are very small. I tried to convince him to correct this error some time ago; he doesn't want to for some reason.

And Chris Long doesn't mention the fact that the closer the bore axis is to the center of the butt pad, the less barrel whip there'll be. And just because he says a rifle with a high cheekpiece will have a lot of barrel whip ain't so. Not if the barrel's close in line with the butt plate's center, where on most correctly built long range rifles, it is.
 
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