7.62mm L4 series........

[TactAdv]

Breech blocks....... Supposedly, a .303 breech block is said to work by simply fitting a 7.62mm extractor!

Yep! As stated here several times lately, a std .303 bolt will work just fine after you install a std 8mm/7.62NATO extractor. If you don't care about historical replication of the L4 mechanically, you can be up and running shooting .308 perfectly with three drop in parts:

-7.62 extractor (installed in a std .303 bolt)
-South African/DENEL 7.62 NATO BBL
-Bulgarian ZB39 mags ( filled to the 25rd capacity)

I must point out though, that this recipe is based upon you being able to source all three of those parts......which is not always easy anymore......and then, that this is based upon their installation into a factory original (uncut) machine gun receiver. Any variation upon that originality, such as a welded receiver and/or re-built to semiautomatic-only function......may impair the "plug-and-play" compatibility of the above parts. It will undoubtedly be able to make it all work, but custom fitting of the various interfaces will likely be required.

It does work flawlessly in an original factory gun. Not an "L4", but that isn't the goal with this recipe.

-TomH