Happened to me about 25 years ago, javelina hunt with a 700 SA. Gun was clean, Neil Jones had done the trigger.
Took the safety off, went bang. Guide turned around and gave me a look I’ll never forget.
The Walker trigger problem was not as well known at the time, no one believed I hadn’t touched the trigger. Hell I was doubting myself until I read up on it. Never happened again. Couldn’t duplicate it.
Still have the gun, should probably get it replaced.