I will be shooting my 300 win mag, and i bought a lead sled.
I know this is a dumb question, but do I need an actual bag of lead for correct weight/mass, or will 3 or 4 lead bags filled with sand do the trick. They are available at the range.
Thanks,
W.

I find several sand bags to work well with my 300 RUM and 338 winchester

pile them on, as long as the forend isn't tied down it won't damage the stock.

I throw a pair of sand bags on mine. Never weighed them but I can shoot my .300 all day and barely notice the recoil. Feels like a .223 to me.