I always tell people that confidence is more important than any features of their weapon. As an example, there's Mordechai Rahamim. A paratrooper selected for airline security duty, his aircraft was attacked by four terrorists 2/18/69. Rahamim leaped from the airliner, engaged the terrorists-who were using AKs, grenades, and leaflets (terrs-what are ya' gonna' do?). Using his Beretta .22, Rahamim suppressed the terrorists, killing one, then engaged them hand-to-hand and made a sincere effort to throttle one. Local security forces intervened at that point.
The details of tactics and equipment are less important than training and confidence.