Harrison lathe

[7745Harrison]

Hello, I have an old Harrison lathe most likely from the 1960's.  Decided to give it a clean up and paint and I noticed this mark stamped into the bed, I know the broad arrow indicates MOD, but does anyone know what the letters might signify?  I'm struggling to make out the letter on the left.

Thanks!

[ruxy]

Unfortunately you don't give a scale rule against the stamp.  If it is approx. 1/2"  across the oval - then it looks a typical  3rd party (probably apointed by the MOD) inspectors pass off stamp .  The broad arrow stamp would b e avoided unless it was on govvy business. The indent brand is poor but the markings would give 'traceability' to the company ,  a unique personal mark for each inspector.  On a quality or toolroom machine tool - you can expect several stamps.  These would be governed by  HOLD points ,  such as a check of the bed casting after machine , any induction hardening of ways - to confirm OK for next stage , this would be scraping (mottling) of bed & tailstock, fitting of headstock then - running of 'reference' cylinders using dti's.  After all fitting work , you could expect finished work inspector / chargehand fitters stamp for functional check of all controls.  I would have expected Harrisons to always employ a outside 3rd party inspection for the final 'pass-off.'   For substantial government contracts - all this is determined at a 'pre-manufacturing meeting'.   They could of course accept a  "Certificate of Conformity"  that more or less just states the goods meets out in house standards and any relevant national standards.   I have even had to recheck hardware and documentation for Russian & East German power presses & found all in order - then rubber stamp + bray my hard stamp with a 2 lb hammer.