Laz:
If I may wade in here. Many know that I really don't step forward with out doing a goodly amount of research. I researched both the 6.5 Grendell, and the 6.8 SPC. If I am really honest, when I started the race, I was betting on the Grendell, however in the end, the 6.8 SPC won out.
Before we start, we may want to look at the "design purpose" behind each cartridge. The 6.5 Grendell was born out of the desire to have a mid to long range "bench rest" accuracy capable cartridge, out of an AR platform.
The 6.8 SPC, according to my research, was a grass roots movement, at troop level, to have a cartridge that was more effective at hard target penetration, yet have all the benefits of handling that are associated with M4 style platform.
So in essence we have here the desire for a Tac-Driver, and a Hammer, out of the AR platform.
With pedigree out of the way, we can not turn to the more practical aspects of actually shooting these rifles and carbines. When shooting as a civilian, one needs to have a really hard look at the supply chain. As far as I know, there is little to no commercial support for the 6.5 Grendell IN CANADA. The owner of the Cartridge, I believe Alexander Arms (correct me if I am incorrect here) has what would be considered a strangle hold on the cartridge. They developed it, and in my understanding, are the sole source for cartridge specs, carbine parts, and brass. I understand that the owner (his name escapes me now) Is incredibly helpful, and will share the wealth of his knowledge. He really wants his cartridge to succeed. Now if your south of the 49th, this is great, however Canada is not. As a result, You have to be a very dedicated individual to chase this one down. and make it happen. There are some on this CGN board that have, and I understand that they have done so with great success.
The 6.8 SPC is another matter all together. There is actually Factory ammo available for this one, and for the re-loader, (like me) components are much easier to come buy. Just so we are clear, the 6.8 spc uses .277 diameter bullets that range from about 90 grains on the light end, to 115 grains on the heavy end for AR use. There are heavier bullets available, but they are not meant for the AR platform.
Further there is some very good commercial support for this caliber. In ammo, any deal that deals with Remington ammo should be able to order it in for you. For Rifles, Carbines, and other build components, one need look no farther than our own Arms East.
For mags, while the 5/25 profile is more or less unavailable these days (this is the same as a 5.56 Nato 5/30 profile) Questar has a large supply that is currently available from C-procudts on the 5/20 profile.
Before any one asks, there will not be any P-mag's for the 6.8 cartridge. I have had lengthy discussion with Justin over a Magpul Technical, and the 6.8 is a fatter cartridge (based on the 30 Rem) and there is simply no room for the thickness required for a polymer mag to still be durable, and be able to feed the cartridge at the same time. So the 6.8 is strictly a "metal mag" cartridge. The up side of this however is that MOST 6.8 spc mags are made out of stainless, which in my opinion has some real advantages.
And before you ask, yes I do own a 6.8 SPC carbine, however as most you know, Im never satisfied buying a factory carbine or rifle. I started with a stag upper from the use market, replaced ever part on it except the barrel, then ordered a complete lower marked in 6.8 SPC from Arms East, and tailored it to my own personal tastes. I am currently in load development phase, so I can not honestly give an opinion as to how it shoots, however, the work to-date shows some very good promise. My carbine looks like this:
I hope this helps, and if I can, I will answer any further questions you might have to the best of my ability.
regards and all the best
AbH
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