hang fire - Phrases/Idioms
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Delay, as in The advertising campaign is hanging fire until they decide how much to spend on it. This expression originally referred to the 17th-century flintlock musket, where the priming powder ignited but often failed to explode the main charge, a result called hanging fire. [c. 1800]