I wouldn't say that 6000 Al is falling short, but it is my understanding that 7000 is stronger and more wear resistant, so I always choose it over 6000 whenever I can. A handguard (or RE, receiver, optic mount, flashlight, etc) can be made lighter and still be just as strong, or the same weight and be stronger. Wear resistance can come into play with a bare handguard, also.
If I am wrong, let me know.
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