I have studied in some details pole&barn paradox and I thought I could solve the following paradox, but sadly I couldn't! Please help me with it so that I can understand special relativity better. Thanks in advance for any help. The paradox: There are two trains T1 and T2 of equal proper length "L" (say) running on two parallel tracks in opposite direction with a relative velocity V such that due to length contraction one appears of length L/2 w.r.t. the other. Train T1 has a gun right at the "back end" which can shoot perpendicularly right towards the track of train T2. Suppose, it has been arranged for the the gun to shoot "as soon as" (has to be defined properly, I guess) the front end of T1 coincides with the back end of train T2. Now one can see that in the frame of T1, T2 will appear contracted (to L/2) so that T2's front wouldn't have crossed the back-end of T1 when gun shoots, and thus gunshot will not hit T2. But in the frame of reference of T2, T1 will appear contracted (to L/2) and thus, the gunshot will hit T2. So is T2 hit or not hit?