EMER C-308 Section 13, paragraph 6 (the Briitish Army bible in relation to No1 rifles) states:
All sub standard rifles are painted with a two inch aluminium band around the fore-stock and the front handguard between the outer band and the nose cap.
There.......... you are the proud owner of an ex BritishArmy sub-standard No1 rifle.
If you or anyone else is really interested in the gauge limits for firing the sub standard rifles, ask and I'll repeat them