Home Forums Hunting & Shooting Ask The Gunwriters Mule Deer -- .30-06 and .300 H&H

Not the expert on pitching you appear to be. I agree a pitchers curve may not be the best analogy here.

I am thinking however that if the pitchers arm moved much slower, the batter would read that like a stop sign. Again, not an expert but the energy put into the pitch by the pitchers body should be similar.

I understand that speed can effect the curve, know what laminar flow is, need to look up magnus effect. Do you dispute that curve balls can't be thrown as fast when the same total energy is applied? Actually, you are saying that in your first sentence and picking on my example at the same time. Don't worry, I have thick skin.

Ok, another ball example. Did you ever see a ball with a lot of top spin hit the ground and then take off at a higher speed. The rotational energy changed to linear motion. The converse can also happen, a machine can be set up to change potential energy to varying degrees of rotational and linear motion. You can change speed simply by applying the total force differently.

Please review your aerodynamics, laminar flow does not happen around a sphere which is a horrible shape aerodynamically.

I dunno, I just aim and shoot.

My view is quite different. There are two types of energy imparted upon a bulley upon firing. One is forward momentum and one is rotational velocity. They are absolutely independant of each other.
While you can say how many inches a bullet will travel per rotation at the muzzle, it is not linear, as a bullet sheds its velocity.
Bullets lose their rotational energy much slower than their velocity in flight.
I believe bullets fired from faster twist barrels expand more readily.
A bullet fired from a faster twist barrel can kill an animal faster, not because of the amount of rotation inside the animal, but because it is more likely to end up being larger in diameter.
It is my opinion that the 300 mags can and often do kill better because with higher impact velocity, additional expansion can be expected and even with the same twist rate the bullet will have more RPMs additionally aiding expansion.

SAWBUCK: Thank you, that is precisely what the article says. Wish they'd just read the article.Guess they're afraid they might learn something........

Stray Dog: Terminal Twaddle is, I think, your definition of anything you don't ubderstand,which from what I can gather, is quite a bit.

I should have proof read,but didn't;should have been,

If a rifle is in a 1 in 10 twist the bullet is only going to turn one revalution for every 10 inches of travel and it's rpm's are relavent to velocity

jwp: thanks for clarifying that. Been scratchin' my head over the 10 vs 19 deal.

For what it's worth...

From Noslers website under the "Did you know" facts;

"Did you Know?
A bullet that comes out of a 1-10 inch twist barrel will make one complete revolution for every 10 inches it travels, even after leaving the barrel, regardless of velocity."

One would think they know their stuff...

[quote=99Lover]
A bullet that comes out of a 1-10 inch twist barrel will make one complete revolution for every 10 inches it travels, even after leaving the barrel, regardless of velocity."
quote]
Very refreshing, a reasonable comment.

When it leaves the barrel it will be 1 in 10.
Not so downrange.

How can it be any different?........

Rotational energy is not mechanically connected to the energy used to propel the bullet forward once it leaves the barrel.

It takes alot of energy to move a bullet through air and it sheds that energy at a greater rate than the rotational energy because not much energy is required to spin the bullet in flight.

If you look at the petals on a Barnes bullet where they are bent due to the rotational energy, you can see that they might actually stop the rotation of the bullet due to drag.

Ask yourself, what is the likelyhood that the bullet stopped moving forward at the exact same instant the rotation stopped and also maintained the 1-10 ratio to the very end.

Not likely and they are not connected.

And how is this going to cause the bullet to spin at a different rate than 1 turn in 10?.........As long as it was shot from a 10 twist..........

Barrel twist rate will only give the bullet a starting RPM.

The higher the velocity, the higher the starting RPM.

It's pretty safe to say that RPM will not increase but only decrease down range.

Does that make sense so far?

Yes and that is what I stated earlier it will be 1 turn per 10" of travel and this is velocity related..........

RPMs will indeed decrease... revs per linear foot travelled will not, until such time as the projectile departs "controlled flight"..... john w

Exactly...............

Forward energy caused by the gasses pushing the bullet is one kind of energy. We know the bullet slows down due to having to plow through the air.

The barrel itself takes a tiny bit of that energy and transforms it to rotational energy via mechanical means.
As long as the bullet is in the barrel it will match the described twist rate.

Once the bullet leaves the barrel it is subject to other forces like air resistance.

Twist is no longer mechanically tied to the forward movement.

In other words, air, flesh, water, etc. can impact rotational energy more or less than it effects the forward energy.