ok my bad on interpreting your previous post then. I thought you were stating that the stress caused by moving the shoulder back to far was weakening the case metal. Now I know my head space was definitely on the short side, last eve I put the go gage in and felt more than normal resistance which I corrected. After resetting the headspace it closes with no resistance on the go gage, but 2 pieces of scotch tape on the end and it would have to be forced. Could a short head space cause a weakening of the case metal in the middle of the case ?
For what it matters my neck sized cases are 1.838, SAMMI specs are 1.840. I reload to a COAL of 2.260 which for my barrel is .080 off the lands. A bit of a jump but it works so I have not messed with it. I don't own a case comparator but I guess I should. I just did a full resize on the new cases then and since use a Forster neck size die
Oh and on the powder load here is a link to a Sierra reload data page where it shows up to 25.1 grain loads of RL10 is a safe load using a 26 inch barrel. SInce I did my load workup I have never used more than 24.5 grains + or - 0. All loads are trickled to weight to a scale double checked against a beam balance