No, the reason that more men succeed in committing suicide is because the men who try are actually serious about it.
Women who "attempt suicide" are often sending out a cry for help. The people who half-heartedly try something need and want the attention. They want to make a mess and have people rush in and care for them. They want to put a punctuation mark on the drama that is occurring in their life and elicit some change.
The men who are shooting themselves just want to get out of their suffering and finish themselves off. They don't want more attention or more help. It's sometimes not easy to slink off and quietly commit suicide before someone intervenes. Someone who succeeds in this task is "dead serious" about dying, not summoning help, or causing more drama.
That's the whole reasoning behind the methods and the severity of attempts. Perhaps there is a gender divide, but only because of the differing motives and end goals.