The Big Bang Theory Season 5 Episode 14 : The Beta Test Initiation
Leonard and Penny have started dating again. Anxious to avoid the mistakes of last time, Leonard suggests they have an Alpha test relationship: rather than getting angry with each other, they'll simply report any 'bugs' they discover and fix them. This goes poorly due to Leonard giving Penny an insultingly long list of her faults, although she remains calm about it. When he tries to patch things up by taking her target shooting, he accidentally shoots himself in the toe. Afterwards, Penny reassures Leonard that their relationship is progressing smoothly.