You don't have to *do* gage R&R on anything. You can use other studies.
The point is MSA as a high level system has to be considered. Basically you address all gages, etc., which you take measurements with which 'affect quality'. In the case of inspection and test gages, typically Gage R&R is part of the standard studies.
You start hitting touchy ground when you want to do an R&R on one gage as evidence of family 'compliance'. If you want to get down to the nitty gritty it can be, and often is, argued that a study has to be done on each gage used for inspection and test on the actual parts and with the actual operators - this is quite often the case.
And you have to look at the family of which you speak. Are they all the same brand from the same manufacturer and are they the same model (etc.)? I saw one situation where a 'qualification by similarity' failed.Same gage and model but one was 5 years older than the first. From that there were/are a lot of reasons why they may *not* be alike.
We come back to common sense and an implied understanding of MSA. As you go through design (
APQP) youi have to look at the situation as a whole - What precision is necessary, etc. This is where you decide what you have to do to 'prove' your measurement and test equipment as well as the environment it is used in and such.
You have to be ready to explain to the auditor what you're doing and why. Proof (studies) may or may not be in order, but it appears auditors are wanting more and more evidence - so specific, extended studies will probably be more important in the future.
Can you '
qualify by
similarity or
family'?
Yes - if you have good evidence that your hypothesis is true.