Set Headspace too far back on 5.56

MMH

Sergeant
Full Member
Minuteman
Mar 17, 2013
303
49
Was not careful & set headspace back to 1.445" on my 5.56. Normally set to 1.455" which is about 0.003" looser than the chamber in my AR. I suppose the only consequence will be reduced brass life for these. will accuracy suffer? I use my AR for PRS, so accuracy is a concern.

EDIT: was not careful typing either. Fixed the numbers to what I actually did.
 
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What tool(s) are using to get your measurements?

1.455-1.457” is my casehead-shoulder reference measurement when using the Hornady headspace tool for all of my 5.56 rifles. Fired brass measures 1.459-1.461, depending upon which of my ARs’ fired brass is measured.

1.555” is the dimension i size my 6.5 creedmoor brass, again using the Hornady tool.
 
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Was not careful & set headspace back to 1.445" on my 5.56. Normally set to 1.455" which is about 0.003" looser than the chamber in my AR. I suppose the only consequence will be reduced brass life for these. will accuracy suffer? I use my AR for PRS, so accuracy is a concern.

EDIT: was not careful typing either. Fixed the numbers to what I actually did.

13 thou will prolly cause casehead separation.