One problem with Firearms is that there was an actual loss of interest, vocal or otherwise. Even the original proposer, TheHurt, has left. Part of this is due to it being an early proposal and thus affected when Area 51 changed drastically, and part of this is due to the "disruptive comments""disruptive comments" that shaped an impression of what people had to deal with there. The history probably doesn't have a sharp of an impact on the lull as the fallout that it had caused.
It's difficult enough to handle a proposal when it's not catching attention. When you also lose the people who are responsible for bringing attention, though, you're effectively starting at a severe disadvantage. Missing a huge chunk of the original support for the proposal means a lot more promotion will be necessary.
It's not going to be a complete solution to this problem, but you really need to get increased promotion to overcome the losses. Don't stop at getting friends and associates, get friends to get their friends. This proposal will have low hopes until it can make up for all of the lost ground.