Changing headspace dimension

[HiMtnHntr]

Any of you ever ran into a rifle chamber that grew a bit of headspace? The particular rifle in question is a Christensen Ridgeline 300 wsm. The fire formed brass is measuring about .003 over what was previously fired.

I should mention that the previously fired brass is Norma and the more recently fired is Nosler.

Thanks for any insight.

 

[WeiserBucks]

It's likely your brass reaching closer to the full dimension of the chamber after a few firings.

 

[HiMtnHntr]

I should also mention this is all 1x fired brass.

 

[WeiserBucks]

Different brass will stretch and form to the chamber at different rates. Proceed as usual you have nothing to worry about. Growing headspace is almost impossible outside of the barrel coming loose, severe lug setback or poor measuring tools/techniques.

 

[wapitibob]

My brass moves almost .020 over 3 firings, last firing is .003.