The Johnson had a tendency for the firing pin to stick in the out position and cause the rifle to slamfire out of battery. I personally experienced this happening. The stock dissintegrated as the bolt slammed back and bent the action. Bits of brass and wood went everywhere. As luck would have it I was in the process of cocking it and did not have it on my shoulder or I would have most likely lost an eye. The rifle had just been fired by two other people.
For a 1941 Johnson to slam fire there has to be a broken firing pin or a missing firing pin retainer and it also has a firing pin spring.to keep this from happening
I disassembled my own rifle again tonight to confirm that the firing pin is completely retracted through the camming action of the two piece bolt,this retracts the firing pin as soon
as the bolt unlocks,also assisted by the firing pin spring.
I bought mine a year ago and as with every firearm I buy I do a complete disassembly to check for any problems it may have,another thing I do with my semi's I make a dummy round
with a live primer NO POWDER of course and cycle it through the action a number of times and check if the firing pin leaves any marks on the primer,the Johnson leaves absolutely
no mark on the primer so in my opinion it is safe to shoot,which I have done,maybe 100 rounds so far but as the weather gets nicer I will certainly take her out again,love shooting the old girl,very innovative design of locking that lives on in the AR15 and a number of other rifles.