I just finished my new brick column to support my pellet trap(s) at 30 yards from my shooting bench. I carefully used my steel measuring tape to locate 10, 15, 20, 25, 30, and almost 35 yards from my shooting bench a couple years ago. I put a 12 inch square paver at all but 25 and 35 yards and those got brick columns. A big oak fell down shifting the 25 yard and I started shooting a lot of targets at 30 yards. I've using my movable support made from an old brake caliper and some pressure treated scraps but I decided to upgrade the 30 yard to a brick column yesterday. It would have been a one day project except for the effect of my 69 years on my stamina. A bag of concrete is the base of the column then recycled bricks then a 24x24 concrete paver on top. That was heavy. I used a 16x16 on the earlier columns but wanted more space for two traps at a time. I lift the traps for multiple reasons but a big one is to protect my dog. They are above her height even though she normally has sense enough to stay away.