I am new to shot shell reloading and am currently only using published loads. Mostly I am tinkering with short shells so loads seem pretty light. In a couple of cases I would like to increase either the powder or shot slightly (not seeking an anti-tank load!). It occurred to me today that one of the things about short shells is that they frequently won't cycle a semi-auto. I know that there are different burn rates and that the pressure profile is important.
Would it be a safe method to make small incremental changes to a load and test them in the semi-auto if I stopped when there was just enough pressure to cycle the action? Given what I am working on, other factors may prevent the pressure from even getting that high.
I just want to be safe and not have to buy any replacement parts (or fingers!).