Before I got into reloading, I read everything I could in the topic and one item that popped up repeatedly was, "don't buy reloads from someone you don't know/trust.
The primary concerns were double powder throws (big boom) or a skipped powder throw resulting in a squib, with the subsequent round blowing the barrel.
https://en.m.wikipedia.org/wiki/Squib_load
https://squibloads.files.wordpress.com/2010/04/squiband1911.jpg
ALWAYS wear eye protection.
I scored a deal on a used Glock 23C. The original owner fired a squib. He decided to clear the barrel by using a high speed steel drill bit. Destroyed the factory Glock barrel. To my delight, he replaced it with a Jarvis barrel. The case head is fully supported. The brass is reloadable instead of slightly ballooned at the case head as is typical of a Glock barrel. I run 165 gr in all of my 40 S&W. The 180 gr just slams the frames unnecessarily. It's my only Glock.
The possibility of a squib seriously challenges the standard tap-rack-bang drill. Only do that if you are in a real shootout. Otherwise, be sure to inspect the round that only clicked! One hopes to see a complete round in there ...