Probably my AR. Not because I believe it is the best weapon out there. But, I do believe it is the platform I am most capable with after being in the military for 21 years.
Ruger SR1911, Colt 1911, Glock 17, Glock 21, Beretta M9, Ruger GP100, Ruger LCR, SW M&P15, Lee Enfield 303, Savage .22, Ruger 10/22. Guns the great equalizer.