I believe that this is related to something called hyper-masculinity I believe that the testosterone in males are also responsible for why there are more male shooters. This shows that it is a biological thing and has happened throughout history. Every violent things all involves mostly men no matter what setting it takes place, dating/love, war, competitive games/sports, money, fame, and survival. Only if it involves some sort of loss, hurt, or hurting their pride. However, ALL men are not like this. ONLY those who are incapable of handling the mental/emotional stress, those who are delusional, those that have "guts" and sinister courage JUST to defend their pride from being attacked, which can be summed up as mentally ill. I will refer back to toxic masculinity, most boys with a certain level of mentally illness tends to not get help and are are not as open. This tend to make things worse, and their aggression can turn to physical violence. Girls on the other hand as mentioned are more open and more capable of achieving this help, and will often have other ways other than alcohol/drug abuse to help distract them.

There are many many many many factors, and it's nearly impossible to list them all. But the general reasons to why there are more men shooter or just male criminals then females is as mentioned biological, psychological, and social factors.