A few days ago Confederate Yankee wrote that Remington were not developing a 6.5mm cartridge. This contradicted what Adam Heggenstaller reported a couple of weeks ago. I checked with Jessica Kallam (Freedom Group – Remington’s parent company), and the statement Confederate Yankee posted on his blog is the official statement regarding the ACR and 6.5mm round …
We are not currently in the process of developing our own 6.5mm round for the AR platform. We have mentioned the 6.5 in our communications on the ACR simply because that platform is capable of handling the Grendel or something like it. At this point, there are no plans to chamber the ACR for the Grendel. However, that may change if we receive enough input from the marketplace to make it seem necessary.
Remington Military Products Division still list it as a caliber on their ACR webpage.
Many thanks to rootman for sending me the top link.
The .260 is a necked down .308. It is comparable to the 6.5×55 Swede, a full power cartridge, not an intermediate such as the 6.5mm Grendel. ↩