I had the same question I have a mid length gas system so I am probably going with a 12.5, 12 or a 14 if I find a good deal. Seems like longer is more weight I would think the only use of having a longer 17inch or 16inch would be if you wanted a more stable bi pod at the end of itBuilding my first Grendel from an 18" barrel I traded for recently.
I plan I hunting with it so trying to keep it on the lighter side but of course want it balanced.
What lengths has anyone else used on 18" AR builds? Pics would be cool to help with ideas.
Also still digging up info on the basics of the round. I know I will need specific mags, are their mags anyone would recommend?
I seen there are two types of grendel chambers. Is one superior to the other if so how?