Ian of Forgotten Weapons had a kaboom with one.

https://www.youtube.com/watch?v=YDuoj7KR-CA

I would say high primer, even though he said it wasn't. A friend of mine had the same thing happen in a Rossi 44 mag, only the round blew out the side of the mag tube and lodged in his cheek. Broke two teeth. He certified that it was a high primer, and recoil activated.

I always ease the follower down on mine so that won't happen, it has worked for me for the past 20 years. Hopefully it keeps on working. I usually grasp the barrel with my left hand just above the top cartridge (in case my right hand slips and the follower get away) and twist and lower the follower down with my right hand. So far so good.

Steve.........

People who use the Henry at a Cowboy Action shoot are generally very careful to lower the follower under control and gently to prevent a chain fire. The bottom of the tube magazine on the Henry Original is open and the tab moves down the barrel with each shot. You need to keep this in mind, because at some point you will need to move the front hand ahead of the tab as you fire your 10 shot string.