I've always charged one case at a time, visually inspected the powder to charge and then seated bullet. I've always done one at a time but that's just me. I also tend to use powders that mostly fill the case decreasing the odds of a double charge.
The number one cause of death in the 20th century. 290,000,000 citizens were first disarmed and then murdered by their own governments. This number does not include those killed in war.
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