Missing ordnance which was recovered following a public appeal did not contain any explosives, the Defence Forces said.
An appeal over the whereabouts of a possible live Army round was issued on Tuesday.
The possible live ordnance was seen by a member of the public on a walking trail on Lugnaquilla mountain in the Glen of Imaal, Donard.
A white illumination round is about 12in (30cm) long and weighs nearly 7lb (3.1kg). It is used by the military to illuminate an area at night.
Issuing the appeal, An Garda Siochana said the casing may still contain explosive and incendiary material, which would pose “significant danger” to the public.
Gardai said the location is inside the signposted Range Danger Area along Route 2.
The Glen of Imaal, in the western Wicklow Mountains, is used by the Defence Forces as an artillery firing range and a training location for Irish soldiers going on UN peacekeeping missions.
Gardai said the round was seen partially buried in the ground and appeared to have been in the location for “some time”.
However, it was no longer at that location and was believed to have been removed.
On Tuesday, gardai said the round had been recovered following the appeal.
The Defence Forces Explosive Ordnance Team arrived at the scene were deployed to the Hacketstown Area, Co Carlow, to assist gardai.
They arrived on scene shortly before midnight on Monday and found the remains of a left-over casing, with “no explosives found in the object”.
After ensuring the area was safe, the team handed the scene back over the An Garda Siochana and returned to base at 1am on Tuesday.
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