I would also like to know if you're neck sizing or full length as well. If you're neck sizing, might be time to bump those shoulders. If you are FL sizing, pressure, or case length is where I'd start.Sounds like pressure. There are a couple of things that could be at play. If you were seating .02 off the lands you could have had one that was a little long and it jammed in when you closed the bolt. That can cause pressure to go up. Another thing could be the powder being temperature sensitive. When it's hot some powder will generate higher pressure. Like Jcalder said, you can prob drop your charge a little bit and go back closer to the lands to see if the accuracy comes back. What is the round and load you are shooting?
ETA. I know you're not the one with the troubles, just carrying on the thoughts lol