What primers are you using (may have missed the post with this info)? If you tried different types and still have issues, see next question.Definitely not mixing, just was showing that I’ve tried different brass to see if that was my issue
Neck tension I’ve tried approx .001” as well as tried approx .0035” yesterday and same ES. I measure each piece of brass to make sure my neck tension is consistent or close to.
It seems like no matter how careful or not careful I am with my reloading process, it always produces similar ES/SD and then factory comes in at about half the ES/SD. Only thing left is powder but H4350 is suppose to be the bomb when it comes to 6.5cm and the fact I’ve tried it in two different 6.5 rifles makes me thing it’s not the powder
How many rounds (dry fire and live) through the rifles? You may be overdue for a new striker/firing pin spring and it's a cheap part so you might as well order a couple and try a new spring anyways.
If you're not overdue for a new spring, clean and dry the striker, striker spring, and inside of bolt body. You don't want debris, oil, grease, etc. affecting the striker movement.