Testing, testing...

[stanc]

Comparing the 5.56 M855 at ranges of 500 meters and beyond with 14.5" barrel weapons seems to bias the test in favor of the Grendel.

How? The M4 carbine is the current standard individual weapon in the US Army. If 6.5 Grendel were adopted to convert existing 5.56mm weapons, it is reasonable to think that the barrel length would be kept at 14.5 inches. Ergo, compare at that length.

Where is the testing for barrier defeat when the pucker factor gets high? E. g. the truck door or windshield at ranges of 50 meters and less?

The truck door and windshield tests need to be done with ordnance gelatin in order to provide useful information. I figure that no members (with the possible exception of Bill Alexander and Gary Roberts) are likely to want to cope with performing gel tests. Cinder block penetration, OTOH, is very simple to test, and can be done by anybody fit enough to carry and emplace the block and water jugs.

I'm in concert with LR1955 -- your test protocol must meet some significant standards to be taken seriously.

As LR1955 would say, define significant standards. :p

Joe, this isn't intended to duplicate military acceptance testing. All I'm proposing are some informal comparison tests to evaluate if there's any substance to the theory that 6.5 Grendel is good enough to replace 5.56 and 7.62 NATO.

If the results should show results that support the theory, then at that point planning for more rigorous testing could be done. OTOH, if the results don't support the theory, then why bother spending the time to devise more complex (and expensive) tests?