Quote Originally Posted by ROCK View Post
Interesting discussion.

I don't know why, but there is little or no discussion that I've seen, regarding the strength of rear locking semi auto rifles such as the SVT 40, SKS, FAL etc.

All of those designs lock at the bottom rear of the bolt below the axis of the bore and thus would seem to be at more of a disadvantage to the 'parallel to the bore axis', rear locking Lee.
Well I don't know about the SVT 40 but the FAL and SKS have very solid bolts with only small recesses for the firing pin. The SKS isn't considered a world beater for accuracy. The FAL works fine, I've fired several of these of different configurations. Theres not much that can give or compress about its bolt.
The FAL does seem more reliable when broken in well enough to be a bit loose, and when loose it loses some accuracy in large part due to its rear lock up.

The Enfield bolt is a long hollow tube, not a square and nearly solid block.

The Remington 788 is more easily compared to the Enfield, I had one of those when they first came out. there are significant differences but they share some weaknesses. Unless the lugs are lapped into their seats perfectly equal accuracy suffers. Some 788 rifles held up very well while owners of others have complained of lug setback and the like. The 788 has a stronger receiver with less open space at the ejector port, so theres less bullet throw or drill.
Its three rows of lugs are another stabilizing factor.
Like the Enfield its rear lock up limits the power range of cartridges suitable for the rifle.

The Winchester 1895, once chambered for .303 is another rear locking action. It worked fine in .30-40 and .303, but not so well in .30/06. The design had its limitations.