Double ended wadcutters were designed especially to use in high volume reloaders like progressive presses... they could go into the case either way and be the same. If the fit your bore well, they give results that are quite acceptable/

Hollow based wadcutters are generally (but not always) swaged from soft lead. The skirt of the base is thin and malleable enough to expand well into the lands and grooves of any reasonable bore variations and give good accuracy as long as you don't have a rough bore that would lead up. I shot thousands of them through my PPC gun with Douglas barrel and never had a "problem" with leading, but had to clean it normally about every few hundred rounds!

Froggie