3 inch rocket 25lb practice warheads

[spotter]

3inch rocket 25lb practice warheads ,still with bakelite transit caps.They were dug up today during some building works and have survived very well.
Noticed some painted markings remain on them but i have no idea what they mean,if anyone knows please let me know.

 

[exat808]

I believe the monogram "AIS" would have been applied by RAF Armourers. The letters following - not sure if it is "BRR" or similar may represent a station code or possibly a status of the item - the army used BER (Beyond Economic Repair) and BLR (Beyond Local Repair) as status codes for some equipment.
What is the white lettering below?

 

[eodda]

Hi Spotter
The 'AIS BRK'(?) is an inspector's mark. Although inert, these heads were subject to periodic and random inspections in the same way as other explosive stores. When they had been inspected (because they are made of concrete that mainly consisted of checking that they weren't chipped beyond certain defined limits, thereby affecting their weight and ballistics), the inspector from the Aeronautical Inspection Service (AIS) would stencil 'AIS' and his recogonised initials - in this case 'BRK'(?) to show that the particular head was serviceable. I can't make out the other markings but they are not significant.
Regards
Dave aka eodda

 

[jayteepee_1999]

AIS use to be located at RAF Chilmark. They were the bain of my life, always finding something on inspection.