If you roll the ball-et on towel, using a very rough wood rasp, it will impress lube holding cuts into the soft lead. If you use OxeYoke borebutter(stick lube, not cream)it will be sufficient to keep fouling soft for up to 10 shots. Really press on the file to impress it's teeth, deeply.
: Rolling the slugs in this manner, also slightly increases their size so they fit the bore better. They should be a sliding (touching) fit in the bore. If loser than that, they probably won't be accurate.
: This is virtually identical to what I made for 12 bore full choke guns, and my 14 bore Rifle. After finding paper ctg. with RB's shot as well as patched RB, I didn't use this mould except for a test. I bored mine from the bottom, using an 11/16" drill, re-ground to cut a perfect hemispherical nose. My plunger, hollow base, design, is the same dia, 11/16" (.6875") & therefore, the mould is adjustable. It will cast slugs from 560gr. to over 1,200gr. I roll them with a rasp, and use the OxeYoke or other BP lube (stick for press)on it's sides. The light one, 560gr. shots to the sights at 50yds.with 100gr. 2F but took longer to load than a paper ctg.which is only 8 seconds, so there was no advantage over paper ctgs. for a fast second shot.
: The picture Musketman produced above, is idential in appearance to my bullet at it's shortest production. I used the long ones, at 1,200gr. as decoy weights. They weighed 2 3/4 ounces each.