Thread: ? Head Space

Originally Posted by 6x47

I thought the shoulder/ neck junction length were the same on both a std and AI?

Head space is not just one measurement of X to Y , for most applications . Usually it is on the whole of the shoulder , from where the body ends to where the neck starts for rimless rounds .Head space is about more than just pulling the trigger and rifle goes bang , it is about fit/tolerances etc .
As an example at the beginning of the WW1 they had a problem of rounds not fitting easily in rifles because of a lack of tolerances/ quality control , so in effect when you head space a round you are only setting the rifle up to accept rounds that are of X size and no more than X in dimension so that A they fit and B the case will seal the chamber for all rifles . So in effect a Rifle head space is so that you can pick up any case/live round and if you load it the rifle it will fire it safely because it is within the in the accepted range of dimensions .