I know Boolits with grooves are best to hold the paper better. In many cases the cast boolits we use have to be sized to the degree that little of the grooves remain. Some boolits have a long borerider portions with no possible groove for almost half the boolit length. Some use home made molds (like 303guy) with no grooves at all. Is there any way to improve the hold of the paper when there is little or nothing for the paper to shrink into? Possibly rolling the boolit on a file to get a better grip. I have thought you could tumble boolits with a handfull of small screws or nuts to texture the slugs . I don't know if either of these can work. Any other ideas?