
1) Firearm terminology
Found on
https://www.crosswordclues.com/clue/hang-fire

An unexpected delay between the triggering of a firearm and the ignition of the propellant. This failure was common in firearm actions that relied on open primer pans, due to the poor or inconsistent quality of the powder. Modern weapons are susceptible, particularly if the ammunition has been stored in an environment outside of the design specifi...
Found on
http://en.wikipedia.org/wiki/Glossary_of_firearms_terms

Hang fire refers to an unexpected delay between the triggering of a firearm and the ignition of the propellant. This failure was common in firearm actions that relied on open primer pans, due to the poor or inconsistent quality of the powder. Modern firearms are susceptible also. The delay is typically too brief to be noticed, but can be several s...
Found on
http://en.wikipedia.org/wiki/Hang_fire

A dangerous situation resulting occasionally from the use of outdated old ammunition where the primer does not fire upon being struck by the firing pin. The cartridge may fire in a virtual instant or some seconds later. In the event that a cartridge fails to fire immediately upon the pull of the trigger, always count out ten seconds before opening ...
Found on
http://www.hallowellco.com/abbrevia.htm
No exact match found.