08-05-2011, 11:30 PM
Welcome. As you noted, the 6.8 SPC will cover your needs out to 300m just fine.
I wouldn't say there is an optimum barrel length or gas system length for the Grendel, since that would be determined by your needs/barrel length. In a 16", mid-length is what AA offers, and I have one of those. For distance, longer barrels are the way to go, so I would recommend leaning in that direction since you already have a 16" SPC. You WILL be able to swap uppers of course, just like with a 5.56 upper. That will give you configuration choices, where you could have your SPC upper with a 1-4x optic, and the Grendel with a 2.5-10 or 4-16 optic...both zeroed and ready to go.
The next factor will be what type of shooting platform you will use. Bench, or stalking while hunting. If you will primarily shoot from a bench or prone position, you can go with 22"-28" pipes. If you are walking and stalking, 18"-20" will serve you better.
For cutting paper, most people prefer to load their own, but there are several quality loads offered on the market now from AA and Hornady that a lot of people have had good results with. You'll have to see what works best in your set-up, but that will largely depend on barrel quality. A high-end barrel will run you about $200 more than a button-rifled production barrel.
Game as large as Elk have already been taken with a 6.5 Grendel at 405 yds, so I think shot placement and shooter abilities would determine your ethical engagement of animals with the Grendel. The vast array of 6.5mm projectiles available gives you much more selection in bullets than the 6.8 for sure, but you will not be going much over 123gr and getting sufficient velocities. It's a fun cartridge to load for and shoot. Basically, you're getting .308 trajectories out of a tiny AR15 with half the recoil, and a lot less powder. It basically makes needing an AR10 in .308 unnecessary, unless you rely on vast supplies of .308 ammunition.
I wouldn't say there is an optimum barrel length or gas system length for the Grendel, since that would be determined by your needs/barrel length. In a 16", mid-length is what AA offers, and I have one of those. For distance, longer barrels are the way to go, so I would recommend leaning in that direction since you already have a 16" SPC. You WILL be able to swap uppers of course, just like with a 5.56 upper. That will give you configuration choices, where you could have your SPC upper with a 1-4x optic, and the Grendel with a 2.5-10 or 4-16 optic...both zeroed and ready to go.
The next factor will be what type of shooting platform you will use. Bench, or stalking while hunting. If you will primarily shoot from a bench or prone position, you can go with 22"-28" pipes. If you are walking and stalking, 18"-20" will serve you better.
For cutting paper, most people prefer to load their own, but there are several quality loads offered on the market now from AA and Hornady that a lot of people have had good results with. You'll have to see what works best in your set-up, but that will largely depend on barrel quality. A high-end barrel will run you about $200 more than a button-rifled production barrel.
Game as large as Elk have already been taken with a 6.5 Grendel at 405 yds, so I think shot placement and shooter abilities would determine your ethical engagement of animals with the Grendel. The vast array of 6.5mm projectiles available gives you much more selection in bullets than the 6.8 for sure, but you will not be going much over 123gr and getting sufficient velocities. It's a fun cartridge to load for and shoot. Basically, you're getting .308 trajectories out of a tiny AR15 with half the recoil, and a lot less powder. It basically makes needing an AR10 in .308 unnecessary, unless you rely on vast supplies of .308 ammunition.