Search:

If you are worried about drainage material contamination ,all that is required is a decent blinding layer,of sand, on top of the Pea metal /GAP 6 (I forget what exactly).But remember drains do not...

The problem of using drums is that projectile can exit the drum at a different angle to the one it entered at . We also for the 100/200 mtr range just use the bags the rubber comes in as they are to...