Once fired brass is almost never tight at the shoulder. If you are FL sizing, set your die so that the shoulder to head dimension is the same as that of the fired brass. It should chamber just fine, and there will be no issues.
If you want to play with a tight case, to find out what the measurement of a slightly tight case is, just deprime one of your once fired cases and put a single thickness of Scotch tape(.002 thickness) on its head, trimming it so that the only remaining tape is on the flat of the head, nothing over the primer pocket or sticking past the bevel around the edge of the head.
Try it in your rifle, but do not force anything. You will likely not be able to close the bolt. Measure the taped case, write that down, and back off your die a sixteenth of a turn, and start adjusting, sizing. measuring, and trying in the rifle, wiping off the lube for each trial in the rifle, and reapplying it for each sizing. This should let you find out just where the point of slight feel is, and from there you can bump another thousandth for target work, or two for hunting applications.
You need to remember a couple of things about adjusting your die. One full turn will advance the die .071, so when you are trying to work in thousandths you want to turn it so little that you are not sure that you did. If you read about anyone suggesting making adjustments of a quarter or eighth of a turn you should understand going forward that they have scant to no experience with accurate measuring tools, and minimal math skills. Let us know of your results. There are some other details, but this should get you off to a good start.