The titanium firing pin won't increase accuracy or speed up lock time, but it does provide an extra margin of safety. The military uses harder , less sensitive primers than most that civilian reloaders use. The AR-15 won't allow the firing pin to move forward until the bolt is locked up, but it will tap the primer when it closes. I choose to use a titanium firing pin to reduce the chance of a slamfire, and haven't had one in >15,000 rounds using the same firing pin. I do my load development beginning at a charge low in the recommended range (from an authoritative source) and work up, stopping before pressure signs are severe. A full-blow pierce will erode a titanium firing pin (and will erode a steel pin at a slower rate), but minor leakage won't hurt it. A titanium firing pin is not a necessity, but does have its uses.