The decoy flare maker now expects 85% of its revenue and profits to be delivered in the six months to the end of October.
Chemring said the delay was due to “operational disruption” at some of its manufacturing sites in the first half.
Back in September, an explosion at its factory near Salisbury left one worker dead and another badly injured.
Several production lines are now back up-and-running at that site, with the others to return to operation over summer.
Despite the more pronounced second-half weighting, Chemring said its guidance for the year remains unchanged.
“The order book provides excellent short-term revenue coverage for the current financial year and the multi-year nature of some contracts provides good medium-term visibility,” read a statement.
Shares fell 4.3% to 148.4p on Thursday morning.