2008, 6.8SPC PERFORMANCE TEST- follow up report now posted

[shooter_tx]

From what I have seen and the data I have collected:

DMR chamber
1:12 Twist
3 groove will allow for the highest level of performance.

Guys. I have been off the site for a while and am absolutely FLOORED at the amount of work and detail that has gone into this latest report (and I have only skimmed it in its entirety, and read one or two sections to completion).

Saying things like "Kudos" and "Hat tip" don't even begin to express.....

I hate it as having a 6 gr is going to bother me even though I am getting very good performance as I can't help but to think about how much more I could possibly get.

As for the twist rate DocGKR has been saying it was the ideal twist since it has been released to the public and that Cris Murray who created the round felt it was the proper twist as well. You would have thought people would have listen to people that involved with the program. Go figure

Agreed. That said, what do you guys think about RoT beyond 1:12? Do you think 1:13 wouldn't impart enough stability for longer/heavier bullets? What about 1:12.5?

I will say I am also now much more convinced about the effect the chamber has on pressure all things being equal. The leade and throat lengths are very important as well as the angle of the transition from the neck to the leade which is labeled the CONE.

How does everyone else miss that?!?

My bet is the original Murray chamber had that right.

I'd wager you're right. If you'll humor me enough to refresh my memory, is the reason the Murray specs are unobtainable because they are proprietary?

[constructor]

[quote=shooter_tx]

From what I have seen and the data I have collected:

DMR chamber
1:12 Twist
3 groove will allow for the highest level of performance.

Guys. I have been off the site for a while and am absolutely FLOORED at the amount of work and detail that has gone into this latest report (and I have only skimmed it in its entirety, and read one or two sections to completion).

Saying things like "Kudos" and "Hat tip" don't even begin to express.....

I hate it as having a 6 gr is going to bother me even though I am getting very good performance as I can't help but to think about how much more I could possibly get.

As for the twist rate DocGKR has been saying it was the ideal twist since it has been released to the public and that Cris Murray who created the round felt it was the proper twist as well. You would have thought people would have listen to people that involved with the program. Go figure

Agreed. That said, what do you guys think about RoT beyond 1:12? Do you think 1:13 wouldn't impart enough stability for longer/heavier bullets? What about 1:12.5?

I will say I am also now much more convinced about the effect the chamber has on pressure all things being equal. The leade and throat lengths are very important as well as the angle of the transition from the neck to the leade which is labeled the CONE.

How does everyone else miss that?!?

My bet is the original Murray chamber had that right.

I'd wager you're right. If you'll humor me enough to refresh my memory, is the reason the Murray specs are unobtainable because they are proprietary?[/quote:330z9w7x]

I tested a 13 twist before I made the 12x3 and still have it, It will stabilize all of the 110gr bullets and some 130s but will not stabilize the 120 Barnes solid or the GS 105 SP

[HTR]

Gentlemen,

I just put the new 12 twist, 3 groove SS, made for me by AR Performance, through its paces, and I have numbers, targets and two kills to show you. Constructor and I talked about the design of this very barrel for a year, before he finally spun some up, and I am delighted to say that I now own one. It is the finest, most accurate AR-15 style rifle I have ever owned. The fact that it is an "optimized" 6.8 SPC, and given what I've now see it do in the field, makes is that much more valuable to me.

I will be posting the report in a separate post tonight, if I can get all the pictures loaded.

[jpach]

Tag. Very informative

[RugerIte]

This looks like the right place for it as the Link on Wikipedia goes to this topic area.

It looks like this site is an influence on the 6.8 SPC as it gets a link and SSA gets a mention on Wikipedia.

http://en.wikipedia.org/wiki/6.8_mm_Remington_SPC

[6.8 Fan]

Gentlemen,

I just put the new 12 twist, 3 groove SS, made for me by AR Performance, through its paces, and I have numbers, targets and two kills to show you. Constructor and I talked about the design of this very barrel for a year, before he finally spun some up, and I am delighted to say that I now own one. It is the finest, most accurate AR-15 style rifle I have ever owned. The fact that it is an "optimized" 6.8 SPC, and given what I've now see it do in the field, makes is that much more valuable to me.

I will be posting the report in a separate post tonight, if I can get all the pictures loaded.

Anymore of these barrels available? I have the ARP 16" 11.25x5 already and want to build another rifle and the 12 3 really sounds sweet, just not sure what length I want 18", 20", longer?

[marinesg1012]

Contact Harrison at AR performance, they are still listed on his site, I dont know what he has in stock though.... I also have a 1-12 3 groove and it is amazing......

[6.8 Fan]

I will do that, but I do not see any 12 3 barrels listed at ARP website?

[marinesg1012]

it is the SAM-R barrels. http://www.ar15performance.com/sharpshooters1 I would call him and ask about barrel availability

[6.8 Fan]

it is the SAM-R barrels. http://www.ar15performance.com/sharpshooters1 I would call him and ask about barrel availability

No wonder, I was looking for barrels not uppers...lol

Thanks!!