I was getting some very premature pressure signs in my 6 Grendel gasser today, so I cut the range time short and went home to check things out. I found I'm getting .0125" growth at the shoulder - I can't recall ever seeing that much growth, but I don't recall the last time I measured new vs once fired. Is this cause for concern? Would it possibly explain the premature pressure signs? FYI, this is 6.5 grendel lapua brass necked down to 6mm. I did not bump the shoulder when necking down. Pressure signs are extractor swipes and hard extraction - I had turned off the gas as to not lose brass in the gravel, so I was manually ejecting.