Bullet rotation speed on hunting bullets???

[Lynn]

Swampfox
The faster twist rate will put the bullet under more strain and cause it to fragment more than the same bullet shot out of a slower twist rate barrel.The results on an animal are not as dramatic as some would have you believe and all those spectaculor hits causing an animal to flip/hop/fly/slam/explode are more the result of the bullets velocity rather than its twist rate.The 300 whisper/300 win mag results posted above are from actual experience in the field.

Alinwa
I know you like to think these things through and do a little testing.Take a 12 pack of coca-cola in the cans out to your 100 yard range and shoot 6 of them near the base and 6 of them near the lid while video-taping your shooting.
Without telling your wife what you did ask her which 6 shots on the video were the most dramatic.I already know what she will say but its still a fun test.
When my 6BR and 6Dasher barrels get around 1000 rounds on them we rechamber them for the 6mm-06 to shoot squeaks at the annual squirrel wars held each year in northern california.The 6BR and 6Dashers don't launch them like the 6mm-06 at all.After the good ole boys at the nbrsa stole the nationals from the shooters this year we have decided to switch back to hunting and only shoot a few IBS matches this year.We will be at the Squirrel Wars 3 days after it is over shooting the predators feeding on the dead squeaks.Most of the shooters go home on sunday.

On the westcoast we don't hunt out of blinds/tree stands/over bait.Our average shot is 200 yards+ not 80 yards.You won't find 3 hunters using a shotgun in 40 years of hunting.Head and neck shots are talked about alot but seldom seen.If you want to see a deer stand up on its hind legs and dance aim for the head.If your buck is looking at you your bullet will crawl along his skull until it hits the base of its horns and he will stand straight up on his hind legs and paw at the sky.Deer don't have reverse in them so a front shoulder shot ends there ability to run off.If you ever see a buck back up a step or two it was definitely hit.
Waterboy

 

[Doug Casner]

dead in its tracks

Last year I shot a buck behind the front shoulder with a 300 win mag. 180 gr. interbond close 20 yds. He went down like he was shot in the head. I was suprised. I thought you had to shootem in the head or neck to get that effect. I think it was the muzzle energy. I forget how much it wasbut it was a bunch. Like being hit by a frieghttrain. Made me a beliver in a big bullet movin fast.

 

[mturner]

Last year I shot a buck behind the front shoulder with a 300 win mag. 180 gr. interbond close 20 yds. He went down like he was shot in the head. I was suprised. I thought you had to shootem in the head or neck to get that effect. I think it was the muzzle energy. I forget how much it wasbut it was a bunch. Like being hit by a frieghttrain. Made me a beliver in a big bullet movin fast.

Doug,
My father had told me about a long standing argument between a small bullet moving fast versus a big bullet moving slow. Which would have the most killing performance? He figured out the best answer when I built a 30-378. Pushing a 180 grain bullet at 3600 fps, he said the answer was a big heavy bullet moving fast.

Michael

 

[Swamp Fox]

Swampfox
The faster twist rate will put the bullet under more strain and cause it to fragment more than the same bullet shot out of a slower twist rate barrel.The results on an animal are not as dramatic as some would have you believe and all those spectaculor hits causing an animal to flip/hop/fly/slam/explode are more the result of the bullets velocity rather than its twist rate.The 300 whisper/300 win mag results posted above are from actual experience in the field.

Of course when a bullet hit the target there a a number of dynamic changes taking place rather suddenly. The bullet immediatly begains to convert velocity to pressure (shock wave). In bullets so designed, expansion will take place slowing the spin much as a skater extending arms will slow their spin. I can't say how fast spin is lost compared to velocity but in the end I pretty darned sure that shot placement triumphs the advantages of spin/hydrolics shock. Deer flipping are more likely caused by the nervous system responding than any force from the bullet.

 

[Old Gunner]

It seems the comparasions are drifting to very different cartridges and velocities rather than the same cartridge, bullet, and velocity, but from barrels with different twist rates.

When you hold a rapidly spinning gyroscope type top, one with the heavy wheel and slim armature, and manually change orientation of the axis, you feel a very strong resistence to that change.
When a bullet strikes flesh and tumbles the gyroscpocic energy has to go somewhere.
I can't give an exact mechanism for it quite yet, but I feel that the rotational enegry is likely presented as cavitation. Each end of the bullet whipping about in a tight circle. This would greatly increase fragmentation due to side forces working on any petaling of the jacket at the nose, and stress fractures from rifling engraving of the jacket.
The more brittle the jacket, such as the German 7.62 Ball I mentioned, the easier the jacket will crack.

 

[Jim S]

Ah intresting experiment today. I have an 8T left hand twist 243. I fired the bullet into the toilet as it flushed and the water swirl reversed it's direction in the bowl.

End of Discussion!!!!

 

[alinwa]

Ah intresting experiment today. I have an 8T left hand twist 243. I fired the bullet into the toilet as it flushed and the water swirl reversed it's direction in the bowl.

End of Discussion!!!!

nahhhhh, it was just an Ozzie toilet and you scared it...... people/things always revert to native under stress.