0:00 Introduction and History of Underwater Firearms
0:55 Engineering Challenges and Russian Underwater Firearms
2:07 Development, Adoption, and Global Usage of the H&K P11
3:36 Examination of H&K P11: Fired Barrel Cluster and Firing Mechanics
5:24 Unique Features of the H&K P 11: Silence and Sealed Sabot System
7:45 The Electrical System and Battery Compartment of the HK P 11
8:42 Web Gear and Standard Load Out for the H&K P11
9:24 The Secrecy Surrounding the H&K P11
10:16 Conclusion and Acknowledgements

Developed by Heckler & Kock and adopted by the German army in 1976, the P11 has become the de facto underwater pistol for all NATO militaries. It is an electrically-fired pepperbox style pistol with five barrels. Each barrel is preloaded and the barrel clusters are easily swapped - and must be returned to H&K for reloading. Two different types of ammunition are made; DM91 bullets for firing in air and DM101 flechette darts for firing underwater.

Many thanks to Andy at H&K for inspiring me to do this video, and to the British Royal Armouries for giving me access to this P11 to film!