I've not used Gander, but there are two notes of interest on that offer .. 3) One $9 surcharge will be added to orders containing ammunition, and 5) Additional discounts do not apply.
So it's possible that the $10 GMT10 discount cannot be applied to offset their egregious ammo "Surcharge" of $9.
Since the M-14 and M-60 have both been "basically" retired from our arsenal, perhaps the difference between XM80 and M80 is no longer significant. I read one blog where the author said that the "X" means it's re-manufactured .. really .. lol. The only consensus I've found is .. that LC 7.62x51 Brass is excellent for reloading.
This is ________ .. http://www.gunbroker.com/All/BI.aspx...deral+champion
.. Now this bein' a G-rated family site, you can fill in the blank word ..