Miles,
I performed a better test than the one you suggest last summer with the new 55-grain Nosler Varmageddon bullets and prairie dogs. Used both my tang-safety Ruger 77 .220 Swift with the bullets loaded up to 3800 fps (1-14 twist) and a Nosler Varmageddon AR-15 .223 with their factory ammo at 3100 fps (1-8 twist.
The difference in expansion was VERY apparent--with the advantage going to the AR-15. Ranges were from 100-300 yards, and the experiment was repeated many times throughout the day.
John,
I am strictly talking about monos. I have no queston about lead spinning very fast is capable of a lot more splatter because it tends to come undone in even small targets. You probably couldn't measure a difference in expansion with calipers on bullet in that case.
I remain doubtful that spin rate will do much for expansion with monos while I believe that enough RPMs can make a noticeable change in tissue damage. I can see the forces would try to make it happen, but monos are pretty tough to bend or open more if you try to work on a partially expanded bullets. Fully expanded monos probably cannot be expanded more short of hitting steel or something close to that resistance.
It can't help them open "more" because there are physical limitations to how much frontal area a mono is capable of.As you say,you can't spin the apart,and no one is saying that.... they can only expand so much...but it might help them open AT ALL...and especially as distance increases, and velocity falls off.
And of course there is a difference in how much expansion you will get as distances stretch,and velocity declines....sure they tell us that the bullets are designed to expand down to 1800-2000 fps,but they don't say "how much"..and the faster twist can be a factor in facilitating expansion as distance increases.
With any tough,expanding hunting bullets,velocity and faster rpm's go hand in hand in getting desired results.
