How to Calculate Mean Rounds Between Failures?

[Double Naught Spy]

That may be true, but police departments and ammo makers treated the FBI's ammo testing protocols as the gospel for decades, if not still.

Blind leading the blind? Remember when the FBI abandoned 9mm and other lesser calibers for the almighty 10mm and then abandoned it for the .40 and now have readopted the 9mm?

It bugs me when people/government agencies fail to think for themselves. I understand that nobody wants to re-invent the wheel, but when basing a decision on the research of others, you need to evaluate the research yourself to see if it is 1) valid and 2) valid for your needs.

The same goes for quantitative assessments for firearms performance. So you have X number of failures given Y number of rounds. Is it safe to assume there is a relationship between the number of rounds fired or are there other parameters involved? 44Amp touched on this. For example, different ammo, different magazines, maintenance, etc.