Enfield headspace issue?

[ireload2]

The design of the Lee-Enfield chamber and ammunition is problematic.
When the chamber is at it's largest (minimum material condition) and the brass is at it's smallest (minimum material condition) the clearance between the case and the chamber is about .012 at the case head. In actual use the difference is about .010. This is about 2X what is found with other infantry cartridges.
In addition the Lee-Enfield standardized chamber has a shoulder that looks nothing like the ammo and the chamber shoulder can be as much as .067 forward of the shoulder of the ammunition. This promotes stretching of the brass also.
While there are variations of head space they are minor in comparison to the engineered in clearances between ammo and chambers. These clearances combine with the springiness of the rear locking Lee-Enfield design, which dates back to the black powder era, to promote stretching of the case head at the junction of the solid head and the case walls. Insuring there is minimal stretching of the case head on the first firing will improve case life regardless of the actual measured headspace of the rifle.