What is a "double axis firing mechanism" and why should one care to have such a thing?
BTW file your idea with the Patent & Trademark Office.
Run a search of their archives first though to be sure it truly is unique and original and not just currently not in production by anyone. My old neighbor in VA manages the PTOs data collection systems for as much and you would be amazed the stories he'd have toward how basically everything and anything that one can think of has already been patented even as it might not currently be in play commercially or may have been an idea dating back centuries ago.
For more on this go here...
Issued Patents (PatFT)
(full-text since 1976, full-page images since 1790)
http://www.uspto.gov/patft/index.html
Good luck!
- Janq hopes you can make a buck off your idea as age is nothing but a hurdle amongst many