I believe when they made Wipe Out they made it with preservatives intentionally so you did not have to do the procedure of oiling your bore after dry patching it clean...and then patching it dry again before shooting... as target shooters have had to do with previous cleaner as Sweet's 7.62... it left the bore with no preservatives and the bore would rust easily after cleaning... this is where the oiling procedure originated... and not necessary when using Wipe Out but it is the owners choice of what to do...