Ammo Accuracy Questions

[bubbapug1]

He not only said it, but he put sensors on the barrel to measure the oscillations, graphed them, than empirically tested the barrel used and measured shot groups to verify his theory. Its a good book, and not a rehash of gun dogma, but a study with verification or disproval of various theories.

I had to go back a way to my old dynamics, strength of materials, and physics studies and background to follow some of the math, but like I said, he sums up each chapter in laymans terms to explain what the experiment yielded.

[ferretwithacheeseknife]

One of the things I am realizing is that the magazine can make a difference. I have one 10/22 magazine that throws a flyer on the first shot when I load it with 5 rounds. If I load it with 10 it does not. Go figure.

[stilly]

...I couldnt tell you if 115 or 124 grn projectiles would be more acurate. Ill tell you that 115 grainers are capable of higher velocities, which will equate to a flatter trajectory. This really wont translate over to acuracy, since you dont need high velocity, you need consistent velocity if that makes any sense.

If you need to meet power factor, are shooting at long ranges, or need higher muzzle energy for hunting, would all be factors in choosing a 115 grain bullet vs a 124. Plain old accuracy at close range wont be as important.

Yes. Reminds me of physical science when the teach had two ball bearings on a machine and asked which would hit the desktop first, one dropped straight down adn the other was hit and made to fly away from the platform of the machine. The answer was BOTH of them will hit the ground first. The reason is because gravity affects them both the same way. That translated to guns, he said if you hold a bullet and shoot a bullet in the same fashion as this device did the ball bearings, which will hit the ground first assuming you are on a completely level surface and the bullet is shot at a 90 degree angle compared to the dropped bullet. The answer, BOTH of them will be a TIE finish.

So if you have brand x bullets and they are consistant in that they have the same velocity and you adjust your aim to match that velocity, then you can predict where they will hit and you can use that, but if you have a sucky brand that is inconsistant and has high and low velocities, remember, gravity will have more time to pull a slower bullet down before it hits the paper or target because it is travelling slower and thus takes longer to get there, once it hits so what, who cares, but in this case, you will have bullet drops that are a bit larger perhaps.

[CSACANNONEER]

Ammo by itself is not "accurate". A certain ammunition's consistency leads to better or worse precision. Accuracy only has to do with the POI being centered around the POA. Precision has to do with consistently hitting in the same place. So, the only way one make of ammo is more "accurate" than another is if the siting system on a particular firearm is better zeroed for one of the makes of ammo in question.

[bubbapug1]

That's semantics. What we are all looking for is repeat ability as in small groups. Big holes.

If its more than 0.5 Moa for five rounds its garbage.

[Germz]

1 - if we are talking purely about the "bullet" the answer is ballistic coefficient. more on that here: http://en.wikipedia.org/wiki/Ballistic_coefficient

2. accuracy is a two part factor; ammunition and ISOLATED platform. which means (for example) one Glock 17 will shoot ammo x differently than another Glock 17. these metrics are marginal but margins matter depending on your distance.

[LynnJr]

He not only said it, but he put sensors on the barrel to measure the oscillations, graphed them, than empirically tested the barrel used and measured shot groups to verify his theory. Its a good book, and not a rehash of gun dogma, but a study with verification or disproval of various theories.

I had to go back a way to my old dynamics, strength of materials, and physics studies and background to follow some of the math, but like I said, he sums up each chapter in laymans terms to explain what the experiment yielded.

I have the book and just re-read chapter 4 on barrel vibrations again.I will leave it at that.