Dimpled round balls...
09-23-2004, 01:18 PM
#1
Giant Nontypical
Thread Starter
Join Date: Nov 2003
Location: Central Ohio
Posts: 8,561
Dimpled round balls...
I'm not a physicist. I just had a random thought...
If a round ball had dimples like a golf ball, would that increase range, velocity, etc.?
If so, would you sit around, carving dimples??
If a round ball had dimples like a golf ball, would that increase range, velocity, etc.?
If so, would you sit around, carving dimples??
09-23-2004, 02:41 PM
#2
Fork Horn
Join Date: Feb 2003
Location: Columbus Ohio USA
Posts: 225
RE: Dimpled round balls...
I am not an expert but here is my take on why it would not work. With a golf ball, when the club strikes the ball it creates back spin. The dimples enhance the effect of the spin and cause the ball to rise. The more the ball spins the higher it rises. At the same time, any side spin will cause the ball to hook or slice. With a rifled barrel. side spin would always be created and the ball would curve (or at least spiral) rather than going straigt. With a smooth bore you would probably get back spin which would cause it to rise and go further but it may not be the best for aiming (trying to get a flat trejectory). I also bet that over the last several hundred years someone has tried it and the fact that you don't see them today is probably evidence that it is not the best set up.
09-23-2004, 04:30 PM
#3
Join Date: Apr 2004
Location: North Carolina
Posts: 501
RE: Dimpled round balls...
Been there, done that.....I shot up 500 Speer .530's that looked exactly like little golf balls...my rifle was already sighted in with them previously and there was no change in accuracy or POI.
I had ordered 5 boxes of new Speer's off an auction, the seller just threw the 5 plastic boxes into a shoebox size carton with no packing material.
During the week long trip to me, all 5 plastic boxes had smashed open from rough handling, and 500 loose lead round balls rattled, tumbled, and banged around into each other constantly...had dents (dimples) all over them like miniature golf balls.
Couldn't tell any difference from brand new perfect ones.
I had ordered 5 boxes of new Speer's off an auction, the seller just threw the 5 plastic boxes into a shoebox size carton with no packing material.
During the week long trip to me, all 5 plastic boxes had smashed open from rough handling, and 500 loose lead round balls rattled, tumbled, and banged around into each other constantly...had dents (dimples) all over them like miniature golf balls.
Couldn't tell any difference from brand new perfect ones.
09-24-2004, 01:23 PM
#4
Join Date: Sep 2004
Location: Ithaca, NY
Posts: 35
RE: Dimpled round balls...
Finally, a topic on which I can lend useful information...
Buckeye Mike has it right. To be more specific, when you hit a golf ball, the intent is to give some backspin, producing lift. That will happen whether or not there are dimples on the ball (based on Bernoulli's Principle), but the dimples 'catch' the air and create the necessary resistance to improve the effects of that spin. Sometimes, the spin is lateral, causing slices or hooks, or top-spin resulting in a 'worm-burner'.
The same principle works on a round ball bullet, but you are not likely to see much effect if the bullet is dimpled. The reason is the shape of the arc travelled by the bullets. Golf balls move in a fairly slow, high arc. Bullets move in a fast, shallow arc. Also, when the galf ball takes off, it is starting at the bottom of the arc, travelling to the top, then falling back...it travels the full length of the parabola.
A bullet starts out closer to the top of the arc, and eventually falls to the ground. The bullet does not get the benefit of the dimple-enhanced lift on the way up the curve. Add to that the fact that a barrel's rifling causes spin only on one axis, perpendicular to the path, and there is little or no added effect.
Now, if you were to shoot round balls out of a smooth barrel, aiming at 45 degrees, I bet you'd see some difference in the distance travelled between dimpled and smooth balls. You'd be using the full length of the curve and not introducing z-axis spin.
Cheers
Rob
Buckeye Mike has it right. To be more specific, when you hit a golf ball, the intent is to give some backspin, producing lift. That will happen whether or not there are dimples on the ball (based on Bernoulli's Principle), but the dimples 'catch' the air and create the necessary resistance to improve the effects of that spin. Sometimes, the spin is lateral, causing slices or hooks, or top-spin resulting in a 'worm-burner'.
The same principle works on a round ball bullet, but you are not likely to see much effect if the bullet is dimpled. The reason is the shape of the arc travelled by the bullets. Golf balls move in a fairly slow, high arc. Bullets move in a fast, shallow arc. Also, when the galf ball takes off, it is starting at the bottom of the arc, travelling to the top, then falling back...it travels the full length of the parabola.
A bullet starts out closer to the top of the arc, and eventually falls to the ground. The bullet does not get the benefit of the dimple-enhanced lift on the way up the curve. Add to that the fact that a barrel's rifling causes spin only on one axis, perpendicular to the path, and there is little or no added effect.
Now, if you were to shoot round balls out of a smooth barrel, aiming at 45 degrees, I bet you'd see some difference in the distance travelled between dimpled and smooth balls. You'd be using the full length of the curve and not introducing z-axis spin.
Cheers
Rob
