I'm surprised Skeetx has mentioned his "Cheerio" cereal cure used as an on top of shot spacer. I believe it was Mike who mentioned his use of it. I use resin micro beads as a top-off filler. Compressible styrofoam bits can be used as well. In some loads I use a combination of felt and cork wads to raise the shot column from the bottom up. In a 20 ga. wad, 28 ga. cork and felt wads are used as the bottom of the wad tapers and is thicker than the top. In 16 and 12 ga., I'd probably try 20 ga. felt and cork wads if plastic wads with shot cups were used. In 1 oz.TSS 20 ga. loads in 2.75" I use a petaled plastic 28 ga. wad inside of a 20 ga. BP wad as a sabot to contain the shot and raise it level with the mouth of the larger wad. Gil