Plasti Guage should be placed on the bolt face, under a new cartridge case of your choice and then close the action. (Best done with the rifle in vertical position.) If the measure is beyond 6 thou. ,I would want a tighter fitted head space. My own preference is between 2 and 4 thou.

In all likelihood it will be fine, headspace means different things to different people....some are terrified of the word lol.
If it makes you feel any better have it checked by a smith. I recently built a sporter off an M38 barreled receiver and had 3 different bolts checked, all passed. I also have a bunch of M98 target rifles with mismatched bolts, and none pass....but boy do they ever shoot.
If headspace is large and you just shoot factory ammo, or neck size your reloads and don't full length size every time you won't have any issues.
For folks using factory ammo & not reloading the cases, a slight excess in head space ain't a bother. For us shmoes that are reloading, we want maximum case life for our loads. A lot of folk tend to hot rod their loads somewhat and that can certainly lead to trouble with sloppy head space.
Best pic I've seen explaining headspace..... 308 fired in a 30/06
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In all likelihood it will be fine, headspace means different things to different people....some are terrified of the word lol.
If it makes you feel any better have it checked by a smith. I recently built a sporter off an M38 barreled receiver and had 3 different bolts checked, all passed. I also have a bunch of M98 target rifles with mismatched bolts, and none pass....but boy do they ever shoot.
If headspace is large and you just shoot factory ammo, or neck size your reloads and don't full length size every time you won't have any issues.
Best pic I've seen explaining headspace..... 308 fired in a 30/06
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