To check that a homeload is not touching the lands of the rifling, colour the bullet with a permanent marker, chamber the round, extract carefully and check for marks in the ink at regular intervals.
Never use a round that has been neck sized only after being fired in your mates rifle, you may find that it gets stuck!
When bouncing around your garage using your rifle like a pogo stick with a live round in the chamber and your foot on the bolt, ensure that wife and kids are not in the bedroom above and you keep your head well away from the muzzle!!
Keep clean underwear near your reloading bench for occasions like this.
Always do the test in #1 with a non charged round.