other than black powder is just a passing fad, the same is true of any bullet that is not paper patched. . A rebated boattail is an angled base
Grommets are metal pieces that can accept a tear on one side.In order to fix the damage, you'll have to maneuver the tears so they connect the spool of thread piece with the tie-off piece.
And before you ask: It does not mean less content.As of this writing, N-1 for deferred channel is 6965.2117 and latest version is 7369.2118.