bsa1917unter: IF.... as YOU say the heavy sand "is bs for the birds" why do virtually all the competitive bench rest shooters in their quest for the ultimate in accuracy/consistency use it?
I think you are wrong in your contention.
I have shot over bags filled with heavy sand and a person can easily "nestle" their Rifle into the bags filled with heavy sand - I know I done it!
You almost earned a sheesh here!
The main reasons I fill most all of my sandbags with regular very fine sand is it is somewhat lighter and I take most all of my front bags, rear bags and window bags afield, very often, Varmint Hunting - and then there is the "cost factor" ($40.00+ for 15 pounds).
Heavier sand in ones sandbags (that fit your Rifle properly) will aid in obtaining better accuracy (thats why the bench resters use it!)!
Hold into the wind
VarmintGuy