Ninja:
The total spec range was .002"
You've got great advice and questions up above.
FWIW, I make a slightly compressible material that (sometimes) has a spec range that large (+/- 25um = +/- 0.001")...usually it's smaller (+/- 5um)
I have thrown out all of our micrometers after they failed trial after trial. Micrometers were simply not up to the job for a spec range as tight as 0.002".
While you are considering the questions and suggestions above (and posting data so we can look into it further), you may also want to start considering what other tools might be used for this measurement.
Micrometers reading in inches typically have a resolution of 0.0001". That gives you only 21 discrete values in spec. While this can work, you might be better off with a gage with higher resolution (and equivalent or better accuracy).
My product is flexible and can be laid flat...so I use a vertical drop gage now with resolution to 1um and accuracy of 1um. Passed GRR with flying colors (%GRR = 0.6 on a spec range of 50um). For X-Y measurements I use a CMM.
All the same, if you are measuring machined metal (not really compressible) ...micrometers may be appropriate.
HTH,