Don't get me wrong - my favorite training is on the range! Trigger time and group therapy is at the top of my list of best ways to unwind and get out of my head from long days in the office. But, realistically, if that was my only training regiment I'd be missing out on core benefits from strength, resistance, and cardio training that can directly improve my performance on the range.
Here's a quick list of benefits of a balanced training regiment that includes components of weight and resistance training as well as cardio. Yes...cardio needs to be in the mix as well for all my brothers and sisters of metal (the kind measured in fps as well as lbs) :
Strength - Improved grip strength, stance, presentation, and recoil management
Reaction - Reflex improvement, responsiveness, flexibility, and mobility
Conditioning - Heart rate control, reduced recovery time, and timing
Focus - Increase ability to focus, maintain intensity, and think through the discomfort
Stress Inoculation - Improve your ability to respond to sustained stress, and push through