Mars: War Logs

After beating up Fatso at the very start of the game, you will quickly run into a fan among the prisoners who will give you a cracked tube (weapon). Tap to reach the menu screen and find the cracked tube in your weapons tab to equip it with and then tap :xbut to bring up the upgrade/modification options. The only slot you can upgrade on this weapon is the handle, and you should have the required items to upgrade the handle with fabric, increasing it's critical hit chance, and unlocking the achievement for you. It's important to keep your items as upgraded as possible to make your life easier on Mars, so make sure you always check containers, scrap piles, and corpses, for new items to upgrade your weapons and armor with (and also to craft items with).