On Jun 29, 2015, at 7:50 AM, Grimmund <grimmund@gmail.com> wrote:

On Mon, Jun 29, 2015 at 8:43 AM, Ethan McKinney
<ethan.mckinney@gmail.com> wrote:
Wind drag strips it off. In space, you could just glue it on. If you
can build gyros and sensors sturdy enough to withstand the launch, you
could use the space in the sabot for guidance.

You could use gyros, but spinning the projectile is very simple. Depends on
size and type of shell.

True, but when the western units went to the DS rounds, they also went
to a 120mm smooth bore. No rifling, no spin.

https://en.wikipedia.org/wiki/Rheinmetall_120_mm_gun

I am not sure that spinning it will stabilize it in a vacuum. I was
under the impression it acted in concert with air drag. IDK, though.

I was always under the impression that the spin induced Gyroscopic Precession: https://en.wikipedia.org/wiki/Precession#Torque-induced - if that’s true then it’s not reliant on air drag - and it will keep the pointy bit pointed forward as long as it’s spinning.

Of course at high enough speed, who cares if it’s tumbling, ass backward or what ever when it impacts.