Mule man
I went with the 6.8 after deciding I wanted a mid range cartrige that had more umph than the 223 Remington in my AR15. The 6.8 is not without it's drawbacks one being the original chambers (spec 1) were not correct due to Remington submitting incorrect specs. Wich creates pressure spikes in those barrels and limits the 6.8's performance because the ammo needed to be loaded down. However, most barrel makers now use an updated chamber (spec2) and cartige developement is progressing. There are a few different ammo manufactures, Remington being one of them, for the 6.8. Silver state armory being another and they load ammo to higher pressures in their "combat" loads for use in the spec2 chambers. This "mistake" by Remington gave me some pause when I was deciding on what cartrige I wanted. The plus is that the 6.8 was desinged around a carbine lenth barrel which, from what I heard, ment that you get great performance out of a short barrel. The 6.5 grendel being a proprietary cartrige gave me even more pause eventhough claimes of it's excellent balistics intrested me very much.
So wich cartrige will win this debate?? Who knows I decided on what I thought was best for me and I hope you do the same. Oh on a final note I just read a little bit about the .30 blackout cartrige, wich I belive Remington will be offering. A necked up 223 casing to .30cal wich is suppose to be simular to the 7.62x39 ballistically and will only require a barrel change for use in an existing AR15.Same mags and bolt just new barrel. I might have considered this round if I knew about it sooner. Because cost of changing over would have been lower.