No, they are Manufacture view marks, the first stamped at completion of the fine bored stage, the second at the completion of the Rifled stage.
There are four such stamps on barrels produced and fitted while the Inspection Branch was under control of F.E Hart from 1915 to 1922. Attachment 60004These extra stamps were due to the use of parallel rifleing and a P in a heart was added to the nocks.Attachment 60011
The first four View marks around the nocks, were added at seperate stages of Manufacture, the Roman Numeral stamped under the star was added by the Inspection branch, to signify that the barrel had completed each phase successfully and was able to be mated to a receiver.Attachment 60010
( This was the responsibility of Manufacturing Inspectors until late 1915 when the Inspection branch was added to the factory.)
The receiver underwent ten such inspections (twenty on early year rifles) before the breeching up phase, after proofing and chamber final finish, the complete rifle is stamped on barrel and nocks with a Lithgowproof, Attachment 60005 and the fifth view mark is stamped by both Manufacture and Inspection branch,(Early rifles may have up to ten such stamps)Attachment 60009 After completion of sighting and final fitment, the completed rifle has a sixth mark added and the barrel, action,bolt, nosecap and forewood are stamped with a serial number and a final Inspection stamp is added to the barrel by the out Inspector.Attachment 60008Attachment 60007
The barrel on rifles up to 1925 were considered to be the main component and the entire rifles history was recorded on both the front of the receiver and barrel nocks.
In the event of a barrel change the barrel was stamped as a replacement, if a receiver, the S/N was struckout and the barrel number stamped on the receiver. This process was reversed after 1925 and the Receiver became the main assembly.
Attachment 60006
So in the event of a barrel or component change post that period, all means of acurately following the history of the firearm became more difficult (not a care to the Military, they were'nt collectors) other stampings on the timber by Units and Military Districts and Factory/Workshop repair stamps and FTR's were added. (just to add to the confusion.)
If the firearm was subjected to work outside the Military stream, than all means of following it's history became rapidly blurred, unstamped and undated or old dated barrels, incorrect bolts and butts and other parts changed