Re: 6.5x284
QUOTE "Ironically, the .284 calls for a free-bored throat, meaning the rifling begins father down the throat than in a non-freebored chamber. This allows handloaded .284 rounds that are intended to be loaded singly to be seated without impinging on the powder space. However, when Norma standardized the 6.5mm-284 with an overall length of over 3 inches, they insured that 6.5mm-284 rifles would handle long cartridges in both the chamber and the magazine. Conversely, a short-action 6.5mm-284 is not possible and a .284 Winchester can be much lighter, pointing out the specialized nature of these otherwise very similar cartridges."
Wouldn't bet my life on it but I copied this off the Norma description so I would say they are the same.