I just KNEW that you'd come back Alan and others and I know it was a bit harsh............ but......... as JSS was (virtually) starting from scratch, It'd be better to start with a V-W solution than a BritishLeyland solution. After I'd written it, I thought that I SHOULD have said afterwards something like '..... head down, steel helmet on......INCOMING!' I've spent a couple of days reading old trial reports and one that I havce been reading relates to the Enforcer rifle that was subject to some trials by the MoD. I'd be sued if I told you what they said about the PECAR telescope. It effectively said that it and the rifle might be alright for any non robust handling but as a snipers telescope, they'd stick with the other contender, a Tasco (I've never heard of a Tasco but I'm not aware of the commercial world). Admittedly, they didn't parachute container drop them during the trials as they did with the No4T's, L42's L1A1 rifles's S&B, Leatherman and the like.
We also seem to forget that there were many instances where the front blocks were drilled right into the barrels so far in fact, that the fired cases bulged into where the chamber was weakened by the 2x screw holes. Enfield said it wasn't them (naturally) and the civvy gunsmiths who had to deal with the loose pads afterwards said it wasn't them who'd drilled and tapped the holes deeper so as to create a more substantial screwed bond.
It's just an engineering fact that a 3mm (? I haven't got one handy here to accurately measure....if someone can do it for us. From thread root to O.D. of the receiver) is insufficient or at best, marginal thread depth. You can lock it down as much as you like. You can use HT allen bolts but it's STILL 3mm or so of what is effectively mild steel - albeit good quality mild steel.
This could be an interesting thread Al...........