Ralf
Let me throw some things at you. Take your 311291 bullet . Make velocity 2500 fps. That gives us 180,000 rpm. First look too rpm...that means revolutions per minute, yes? According to Lyman time of flight to 100 yard target is .131124 seconds. Bullet is not in flight for one minute. Let us say that it took 1 full second instead of what Lyman say. Then my question to you is did bullet turn 180,000 rpm or did it turn 180,000 rpm divided by the one second which come to 3000 turns?
That is correct; you are dividing the 180,000 by 60 (60 seconds in one minute) to get the RPM of one second, i.e. 3,000.
Let me ask different way. If you could stop bullet right after come out muzzle but not stop rotation, all this for observation purposes, would bullet be actually spinning 180,000 rpm? I think not. Another observation. Guns do not torque very much when fired but they do recoil. If you lay rifle on bench and fire with string would not you think if bullet leaves muzzle at 180,000 rpm that not only would rifle recoil back but spin some too from rotational torque?
If you stop the rotation you are correct, the bullet is no longer doing 180,000 RPM. It is doing zero RPM because you stopped it. I'm not seeing a point to this?
There is in fact torque. Shoot a light weiht '06 with a 180 gr bullet without holding the rifle and you will see the rifle recoil to the rear and counter clockwise. Also ask any big bore shooter if there is no torque during recoil. Yes there is torque. However it is proportional to the weight of the bullet, the spin, the velocity and the weight of the rifle. As I mentioned earlier about higher pressure in faster twists. There is higher pressure as the bullet enters the rifling. That also is where the rifle is torques. Some question whether there is further resistance or torque be cause once the bullet is in motion (rotating) in tends to stay in motion. I'm not really sure either was but as I've said; I've not found any evidence on bullets of increased pressure in the rifle marks on fired bullets.
Someone say bullet leaving muzzle like soft copper wire spun in drill. This is such crazy comparison to bullet, how do I explain. Bullet is not like spinning flywheel. If bullet is really spinning like that would you not think that this rotational force would show up in certain targets like gel test or flesh? Take a flat plate aluminum. Put it on drill stand table but no clamps. Chuck in 1/2 inch drill and set drill rpm for say 2000 rpm. Then abruptly bring drill down fast into aluminum. What happen? Aluminun gets spun very violently. Yet bullets don't show this in target medium.
I think what I am getting at is not rpm that destroys accuracy or bullet for that fact but I think pressure.
That's what most every one thinks. Hoever (once again) Pressure effects the bullet in the barrel. RPM effects the bullet in flight. If there was no centrifugal force from RPM then all bullets, even unbalanced bullets, would fly straight. Of course youstill have the effects of wind on the bullet but it is the centrifugal force of the RPM that causes the inaccuracy.
One more thing think Larry. I have seen test where noses of jacketed bullet were damaged to see what happens. You would think the bend noses would unbalance bullet badly but yet they shot say ok. I don't like that voids unbalance bullet so bad and is amplified by rpm because I don't think bullet is really spinning that fast.
You go think and let us know what you come up with to my many questions.
I don't have to go think. You go back and reread this thread and the first thread, Chapte 1. You will find I purposely unbalanced some .308 bullets and fired "before" and "after" ten shot grups. Study them closely, the answer is obvious.
Damaging the nose does unbalance a bullet but not "badly" Shootin "ok" as compared to what? If they shoot into 1 moa undamaged and into 3 moa damaged is that "ok"? It may be for deer hunting but it is not to a measurement of accuracy.
Larry Gibson