It's hard work, but under their combined efforts Jack eventually feels the door start to budge. Dropping the rock, he backs up a few steps, then slams himself into the door. The remaining ice shatters outwards as Jacks momentum not only throws open the door but sends him sprawling down the short flight of stairs down into the basement. Ignoring the pain, Jack looks up and, upon seeing Grant standing there, snarls and upholsters the japanese officers stolen pistol.
In one quick motion he brings it up and fires off the entire magazine. 8 shots chip away and shatter the ice armour around Grants shoulder, filling the air with glittering fragments of ice.