first US EVA...
Here's the straight poop, from Mark Wade's stalwart Encyclopaedia Astronautica:
"... Over the Indian Ocean, White was ready for EVA at last - hoses hooked up, umbilical ready, gun in hand, and chestpack in place - and they again rested and chatted. Nearing Carnarvon, Australia, they began to depressurize the cabin. Then a mechanical problem arose - the door would not unlatch because a spring had failed to compress. After much yanking and poking around the hatch ratchet, the door suddenly cracked open. White found the hatch as hard to push up in zero g as it had been on the ground.
Once he had it opened, White rose slowly through the hatch and installed a camera to record his movements as he swam in space, with the zip gun, tethered to his right arm. floating freely by his side. White triggered a burst from the gun, rose above the hatch, and, without imparting any motion to the spacecraft, propelled himself away. Experimenting with the double-barreled device, he traveled about 5 meters but found himself higher above the spacecraft than he intended. He wanted to go over to McDivitt's window. Short bursts of the gun worked well; in fact, it responded throughout much as it had in ground training on an air-bearing table, at least in pitch and yaw. White was less sure about roll, which he thought would be harder to control without using too much fuel. Floating freely, he felt a tendency to pitch, roll, and yaw, all at once. He knew the gun could correct this, but he was concerned about the fuel it would take. Instead, he tugged on the tether and pulled himself aft and high atop the spacecraft adapter. White saw the thrusters firing, expelling plumes of flaming as, as McDivitt steadied the spacecraft. White propelled himself away rom the danger - across the top of the spacecraft and out beyond its nose. He use the gun for two pitchovers and two body turns, each time stopping easily. Then the compressed oxygen fuel bottle was empty..."