Glad I could be a source of amusement for you...

and I don't need to change your mind. If you are comfortable with 50k CUP that close to your face and eyes utilizing eyeballed specs to save a few bucks, knock yourself out. Modern metallurgy and machining has spared an awful lot of people that Darwin would have otherwise swept off the chessboard.

You talk about case head separations as if it's an ok thing. I back off when I start seeing primers bulge or extractor swipes. You are wrong about the bolt not closing, depending on the force behind the bolt (and I close mine with authority) and the charge, you jam the lands and force the bullet back into the case when you are short on headspace and light on neck tension. Try that with a fast burning powder near maximum load and there's your hunky-dory case-head separation.

I don't need to see injured people and wrecked receivers on the interwebs to prove what I know. I am an engineer by profession. I don't fool with physics. I control as many variables as I can and using a precision machined tool to set headspace is one of them.

You go do whatever you do...

and unless you know the OP's educational background, skill with tools and generally building anything, the responsible answer is to tell him to use a proper gauge...

Quote Originally Posted by Robinhood View Post
I'm sorry if I find this amusing. How many rifles have you seen that were destroyed by head space being a few thousands out of spec? ZERO.

Misinformation is all over the internet. You could present your position like below but implying that there is going to be a catastrophic event is somewhat irresponsible.

If head space is too short the bolt will not close so it can't be fired. If it is too long it will either have a light primer strike with no ignition or it will ignite and push the primer out.

The worst case scenario would be case head separation but there would be other factors involved. Similar to over sizing brass.

There is no magic here. Head spacing is a dimensional thing. The No Go gauge has an increased length from the base to the datum on the shoulder. It will indicate that the chamber is correct by the bolt not closing or excessive if the bolt does close. A well thought out shim accomplishes the same thing with the exception is that you can control the length separation between the go and the no go. The only thing is you need to have some kind of understanding of small differences in dimensions and how to check them.

Change my mind.