This guide will walk you through the use of UE Viewer[www.gildor.org], a tool also known as Unreal Model Viewer[www.gildor.org] or http://www.gildor.org/en/projects/umodel created by Konstantin "Gildor" Nosov[www.gildor.org]. to extract various contents from games developed by all generations of Epic Games' Unreal Engine such as models, textures, animations and, the subject of this guide, sound.
The tool has many uses and numerous functions to serve such folk as game modders, but for this particular guide, I'll just provide you a straightforward method to extracting audio from the Bulletstorm & Bulletstorm: Full Clip Edition UPK files.

Some good news is that I've been finding an abundant amount of Duke Nukem singleplayer dialogue in my extractions (According to the files, they're basically stored in & loaded via their own "localisation" folder, so it's almost a dub exclusively replacing Gray's dialogue), leading me to strongly believe there's no need to own the Duke Nukem Bulletstorm Tour to get the entirety of Duke's dialogue.

This is heavily based on a previous guide I have written detailing the general use of this tool for audio extraction, which can be found here (With successful results on 18 personally tested games): How to Acquire: The Audio from Numerous Unreal Games.

In addition, I have the original Bulletstorm's PC audio data extracted & available for download here: Sound Collection: Bulletstorm.

You will obviously need the tool itself. You can download the tool for Windows & Linux directly from the tool's webpage[www.gildor.org], as well as find video tutorials for the use of the tool on the tutorial page[www.gildor.org].

This tutorial here may prove similarly useful: http://www.airpressuretendency.net/fcsquad/squadmaps/squad_maps_do_it_yourself.html

The only required files are 'umodel.exe' & 'SDL2.dll'. When you export contents from your chosen game(s) with the tool, it will create a new folder titled "UmodelExport" with the contents within, so you can do either of two things:
- Create a folder dedicated to the tool so that you can neatly arrange your exports/extractions there.
- Copy & paste the tool into the game folder*, as this will both allow Umodel to immediately load the contents without you having to locate the folder directory each time you load it and will export the contents into a "UmodelExport" folder within your game folder, centralising everything to one distinguishable location until you've completed the export of all your desired content. This is my preferred method.

Run umodel.exe, and a GUI similar to this will load:


Simply load the game folder directory if it hasn't done so by itself, and then tick the box for Sound, and assuming you don't want anything such as Animation or Textures, untick the rest to ensure you don't extract anything you don't want.

Bulletstorm is fully supported by Umodel.exe, and with the near identicality of Bulletstorm: Full Clip Edition, you won't need to Override game detection nor select anything other than Auto for Package compression or Platform.

Now that you have the files loaded, it's simply a matter of highlighting your files and clicking "Export". You can highlight multiple files at a time, so the process is far from tedious.

It is recommended as many games store their audio differently (Some may neatly pack them in an Audio folder whilst others may have many UPKs designed to detect the game's audio library, resulting in many duplicates tucked into different folders), you simply go through all of the folders and Export from everything. As you presumably have only Sound ticked, the tool will only search for & export audio files.

Typically, PC Unreal Engine games use OGG Files with the occasional use of WAV for audio as well as BIK files for prerendered video that may potentially contain audio exclusively rendered within it. OGG & BIK files can be played back with such players as VLC Media Player or Audacity.
Should you happen to be able to access the data from an Xbox 360 copy of Bulletstorm, it instead uses a file called XMA, which with the use of ToWAV.exe can be very easily converted (Just drag & drop ToWAV.exe in with your XMA files, then either drag & drop your XMA files over ToWAV.exe or double-click the BAT file usually named "Convall.bat" or "towavConvAll.bat", then if all is well, watch them turn into WAV files). The tool should remain downloadable here: http://hcs64.com/files/towav.zip
I have not personally attempted an extraction from the PlayStation 3 version, but a music rip I've got indicates it should use MP3 files, so those should avoid causing any additional nonsense. At this time, Xbox One & PlayStation 4 remain a no-go, so only the PC version of Bulletstorm: Full Clip Edition is viable for this venture.

In the occasional event a certain file causes an error on extraction, simply see the "notify.txt" to find out which one caused it, then just work around it to ensure the error didn't interrupt your Export from exporting any other valid files.

With your desired audio data exported, you may now enjoy as you please.

For anything beyond personal use, always crediting for use and never adding monetary value to what isn't yours to sell are the most effective methods in ensuring your mod, video, etc isn't taken down.
For information on video monetisation, this should hopefully clarify: https://forums.gearboxsoftware.com/t/youtube-monetization/85060/29. Otherwise, abide by Fair Use and don't place ads upon a reuploaded collection of character's dialogue or the game's soundtrack.

For more guides & audio collections, visit The Bizarchivist Sound Project and navigate through the Discussions.