Has there ever been studys done on twist rate vrs bullet terminal damage ???

Thanks LukeA for the clarification.

Grab a spinning bullet and it's going to go from a few hundred thousand RPM to zero in a short space of time - it's gonna take some flesh with it. The energy may be low but the power could be very high. Power is RATE OF ENERGY TRANSFER. Spread that 'power' over the length of the wound channel it becomes insignifcant.
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Good point. You might (or might not) would lose some skin if you stopped it rotating with your fingers. Subject to LukeA's review, I calculate that spinning 77 grain .223 bullet would release about 20,000 watts of power to your fingers (assuming it only takes 2 rotations to stop). OTOH, that'd be released in only 0.5 milliseconds, and I don't know how much heat skin can absorb in that short period. Copper transfers heat very well, so my guess is that the jacket itself would absorb most the the heat.

As far as relative damage to soft tissue, while the rotation of the bullet may release 20,000 watts, the forward motion releases about 4 million watts (assuming 12" penetration), so even WRT power, as 303Guy suggests, the rotational component is negligible.
 
so... could / does this additional rotational force, cause a more dramatic "expansion" of the bullet on impact, if the bullet is of the design ( like a varmint bullet ) to rapidly come apart ??? I can understand that a good soft point hunting bullet isn't going to "explode" on impact, but perhaps the additional rotation of a faster twist barrel helps those easily frangable bullets come apart more dramitically on impact ???
 
so... could / does this additional rotational force, cause a more dramatic "expansion" of the bullet on impact, if the bullet is of the design ( like a varmint bullet ) to rapidly come apart ??? I can understand that a good soft point hunting bullet isn't going to "explode" on impact, but perhaps the additional rotation of a faster twist barrel helps those easily frangable bullets come apart more dramitically on impact ???
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Let's say that we have a stationary, non-rotating bullet. Let's also say that filling this stationary bullet full of smokeless powder with total chemical potential energy equal to the bullet's rotational KE in flight is a decent simulation of the bullet stopping rotating under extremely high negative angular acceleration.

By my calculation (using 4.62MJ/kg as the energy density for smokeless powder), the explosive effect of the spinning bullet coming to a stop very rapidly are equivalent to filling a small cavity in the bullet with 0.018gr (grains) of powder. That's about 1/10 as much powder as is in one of those party poppers where you pull the string and little streamers shoot out. I don't think the effect will be significant.
 
Seems like there should be some way to test this with a smoot vs rifled bore gun. Of course I guess the bullet shape itself would have to be different, so it would probably not work.
 
The relationships between twist rate and bullet weight

This is not by any means a comprehensive look at the problem but it does examine the effect of twist rate on certain military ammunition. Essentially, the .223 round does more damage when it yaws upon impact and tumbles inside the body. It's more likely to do this when the bullet is just barely stabilized by the barrel's twist rate. You can read the details at http://www.ballisticstudies.com/Knowledgebase/.223+Remington.html. Hope you find it as interesting as I did.
 
Has this thread died? There's some interesting theories in this thread. I kind of hoped that it would keep going.
 
It died three years ago and with typical someone brought it back with their first post on the forum.

The mods will be along to lock it soon.
 
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