cs86 asks:
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Or is it acceptable to have a slight interferance as long as your bolt shuts ok?
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I don't think so. Especially with all factory rifle actions and barrels and most of the custom ones if accuracy is important to the shooter. As there's a bit of clearance between the bolt and receiver, a small amount of slop's there. If the bolt closes on a loaded round exactly the same for each shot, the very best accuracy will happen.
When the bolt binds against a loaded round, the bolt face moves around on the case head. As all factory bolts' face ain't perfectly square with the chamber axis, when the bolt binds on case heads the locking lugs seat at different places. Firing a new case in such situations causes that case head to flatten out against that unsquare bolt face. Resizing that case to reload it doesn't square up its case head. When it's chambered and its' high point aligns with the bolt face high point and the fired case shoulder wasn't set back far enough, binding happens and the locking lugs seat all over the place instead of only one place. And that causes the barreled action to whip differently from the inconsistant stresses set up in the barrel. Bullets leave at slightly different angles relative to the line of sight. Proper tests have shown from 1/4 to 1/2 MOA increase in test group size from such binding.
However, if you and your rifle don't shoot that well, then binding up the bolt in your rifle on case heads may not matter at all.
Top competitive and other accuracy-obsessed shooters reloading bottleneck cases with a full length sizing die use a case gage, such as the RCBS Precision MIC, to measure the case head to shoulder "space" or length on a fired case. Then full length size the case and measure the case again. Best practice is to set the fired case shoulder back about 2/1000ths inch. Just adjust the die up or down in the press until the desired shoulder setback is attained. That gives record-setting accuracy, long case life and all sorts of other good stuff. This is what Sierra Bullets does testing their products for accuracy; very few people shoot their bullets as accurate as they do.