It is EXTREMELY important to understand the difference between corporations which need to follow, say, ISO 9001 or whatever else set of procedures such corporations want (or must) to follow, and individual users of torque tools. In order to pass audits, corporations must renew stickers attached to tools every year (or two years, or whatever), even if these tools were not used at all. Which means doing calibrations, certifications, etc. no matter if it makes technical or practical sense at all. It's all about paperwork and formal compliance with regulations, and some of these regulations are nothing but waste of time. Had a lot of experience with all that stuff...
On the other hand, individuals have no need whatsoever to do the same things, individuals are not obligated to follow ISO procedures, have any "approved" type of paperwork, and can afford, which is really great, just use common sense. Which often does not dictate any need for annual calibration if torque tools are not used a lot. And because torque tools for firearms applications, limited to individuals, are hand tools, which means they are, very likely, not being used a lot (who, realistically, not being a busy gunsmith or somebody involved in manufacturing, is using torque tool 1,000s times a year?), all this obsession with need for calibration of torque tools, owned by individuals for their private use, looks a bit funny to me. The only practical case for calibration of privately owned torque tool is just to make sure that such tool is actually matching claimed torque output, if tool owner has a justified suspicion that it may be an issue.
I agree totally with the above post. Certain uses don't require perpetual calibration.
My expectation, more than actual accurate numbers within 0.05% of claimed, is that whatever setting I pick for action torquing remains accurate the next time I take it apart and put it back one. I guess if you use it 1000 times a year it may need to be recalibrated.
I may be wrong, as I have been that one time in my life :), but ISO 9001 means certification of accuracy and standarization, so that someone in Japan can get repeatable results with someone in the Polynesian islands and someone in Subsaharan Africa. Does not mean that not having ISO9001 is bad, it just means you can't be totally sure.
