The whole construct looks pretty impractical from my standpoint. You're considering a hand-held rocket launcher with multiple projectiles with no vent and no recoil protection for the user. Weight alone would prevent anyone from holding it the way you are picturing it; a major potential for catastrophic injury. Also, shooting from the hip is a rather inaccurate method to aim such a high-velocity weapon even at short range. You don't need a blast shield, you need full body armor for adequate protection. Why do you think the bazooka and the disposable rocket launcher is shoulder held, for accuracy. Just my two-cents.