I went thru this exact same dilemma when I was building my speaker stands. I even posted a thread here in "Tweaking" with a similar title!

Steel shot is way expensive and not worth the expense and trouble of finding/shipping it.
I went to Home Depot and bought a 50lb back of Play Sand for $3. It even says "50 Pounds of Fun!" on the bag.


The bag says "sand is screened, washed and rinsed." It looked clean and bug-free to me. I filled my stands with it. The PVC pipes in my stands are 3" diameter and 21" long. I used about 1/4th of the bag...or less than $1 worth of "quality washed sand". Hahahaha! I crack me up.
Anyway, use sand.

When I knock on the stands it's like knocking on a brick wall. They be dead. (sic).
Hope this helps.
