I bought a used whidden bullet pointer, and I don't know which insert came with it. I want to point some 123 and 139 scenars. On whidden's website it says to use the 0 insert. I measured my sleeve at .2645, so I'm sure I have that right. Can one of you fine folks tell me how to figure out which insert I have, please. The only marks on it are 2 horizontal lines, does that mean 2 insert? Thanks