My brother has a left hand 7mm model 700. We took it to the range when he got it and it fired intermittently as the bolt was closed. Scared the you know what out of us the first time. We kept it pointed down range and cycled a few more rounds. Some cycled fine but a couple more fired upon closing the bolt. We went home and I tore it down and found out the trigger was set so low as to be a literal hair trigger. I adjusted it back to what seemed a safe setting. I wonder if they can “unadjusted” themselves. I’ll let him know, though, that he can get a free fix.
Yes they can.
I had a 700 purchased new about 1990. After firing about 5 rounds though it the trigger pull was right back to it's creepy & slack self.
In addition if adjusted to a 3 pound trigger pull it could wind up firing when the bolt was closed or when the safety was released.
Replacing the factory trigger with a Timney Trigger fixed those problems.