Bolt depth and ejector marks

[WestMOhunter]

[quote=mtnlvr]

ditto on mtnlvr's comment. I am a retired Tool and Die Maker and was required regularly to work to 4 digits accuracy and some tines 6. Calipers, by their nature, do not provide the "feel" necessary to measure to ten thousands of an inch. Depth micrometers aren't much better, so for safeties sake, I would not put a lot of faith in your measurements. Just my two cents worth.

Thanks for the info. Yeah, I have been working on the assumption that there is likely error, but not .0050” on a tool that reads to .0005”. But I admittedly don’t know what standards to expect with a digital caliper from an auto parts store. I will definitely keep that in mind. While relative comparisons and assumptions aren’t rock solid, part of the reason I’ve not assumed significant error is because when I measure .125” bolts they’ve been close (.0010-.0015). Anyway, I will quit basing this off of a caliper measurement. I’ll just shoot with a new bolt, and check for case head ejector swipe. Appreciate the help.