Requirements for Replacement of Currently Issued 5.56 M-855 and 7.62 M-80.

[stanc]

Any rifles and MGs designed for 7.62x51 should be adaptable to the new round.

Of course. However, it would be somewhat illogical to convert the FN FAL and FN MAG, for instance, to the intermediate cartridge, as the only weight savings would be in ammo, not the weapons.

I suggested the FN pair simply because they are the two most obvious ones, being recently designed, in military service, and lightweight for the calibre.

Understood.

[6mm SAW] was a good cartridge for its purpose, but I think that it is probably too small and lacking in power to be a credible replacement for the 7.62x51.

I'm sure you're right about that. But, although I initially started out years ago proposing a single caliber to replace both 5.56 and 7.62 NATO ( http://www.g2mil.com/6mm_optimum_cartridge.htm ), I've since concluded that a two-caliber system probably makes more sense, all things considered. Plus, I don''t see 7.62x51 going away anytime soon; it works well enough insofar as target effects, and there is such a multitude of weapons chambered for it that it doesn't seem cost-effective to try to replace.

Don't forget that I see a new conventional round as being a half-way stage to something like LSAT. I believe that it is necessary to prove the intermediate round concept with hardware people can take out and use, before committing to introduce a whole new technology in the calibre. That means a conventional development path using existing weapons.

If LSAT fails for any reason, then other ways of lightening the load can be tried with the new conventional round - stainless steel cases or part-polymer ones like this one: http://www.pcpammo.com/index.html

Yes, I had forgotten that. Given that goal, your approach is logical.