View Full Version : 6.8 Noveske 7.5 build - FH options

13 May 2010, 14:59
Check's cashed, just waiting to go pending/stamp on my SBR build.

I'll be using a Noveske 7.5 barrel in 6.8 SPC, and I'm trying to avoid the KX3 if it's reasonable. I understand the benefits, but I'd like to avoid the additional weight. The only drawback to me in this build is the limitations of using a suppressor in the future (ie: warranty).

Goal is more along the lines of reducing flash, not so much noise, and the options I've looked at are as follows:

Smith Vortex, A2, VLTOR Vc-302 (short), Troy's new "Claymore" levang style comp.

I'd like to go with an AAC Blackout, but I don't see a non suppressed version available in either 5.56 or 6.8/7.62 on AAC's site (if someone in the know has better info, please let me know).

Feel free to throw some suggestions this way, along with guidance if you have any.

This will be a dual upper build, I'm using a BCM 11.5 in 5.56 for the other. I'm really leaning towards the Ops Inc M4-S for it, BUT, if I could use say an AAC M42K on the 7.5, or the Surefire FA68k, without issues, that's really the route I'd like to go, and use the same can on both uppers. That's IF either the AAC or FA68k will clear the DD Lite 7.0.


13 May 2010, 21:14
Just curious why your going with a 7.5 for the 6.8 ?

14 May 2010, 07:23
I've wanted to do a 7.5 AR for a while now, and the 5.56/.223 round ballistic performance simply doesn't cut it at that size. Sure, there's neat factor along with it, but IF I was going to build this, I wanted it to be practical at the same time. After tons of reading and research on the 6.8, terminal performance even out of the 7.5 is very respectful @ 200 yards. What this will do for me is give me a compact HD weapon, the ability to work in/out of a vehicle quickly, with what I consider to be excellent midrange capabilities as well. Personal opinion, in a worst case "SHTF" scenario, 250yd + engagements would be few and far between in a local urban setting.

The only drawback I see so far in this build is cost of ammunition. I'll be getting into reloading now which will cut cost a bit after the initial outlay, but that will also support reloading other rounds as well. The availability of various varmit rounds such as the new 95 gr Barnes TTSX can extend the 200yd performance. Should Noveske offer the 8.5" barrel again prior to the stamp arrival, I may just add that extra inch, we'll see.

I'll be doing a build thread on the complete rifle, along with chrono times for various rounds, and some barrier experiments at range (windshield, sheetrock, ect). I'll have a 16" LWRC M6A3 on hand as well to compare it with, along with the 11.5 BCM upper.

6. SSA Speer 90 Gr. TNT with a muzzle velocity of 2562fps (8" barrel), will expand from 2000+ fps, which leaves a maximum performance range of 192 yards.
8. SSA Barnes 110 Gr. TSX with a muzzle velocity of 2300fps (8" barrel), will expand from 1800+ fps, which leaves a maximum performance range of 209 yards.
9. SSA Nosler 110 Gr. Accubonds with a muzzle velocity of 2335fps (8" barrel), will expand from 1900+ fps, which leaves a maximum performance range of 204 yards.

14 May 2010, 09:59
I don't think any company recommends their cans for under 10.5" on 5.56 or heavier.

I would go with a KX3 if it were my blaster. With that short of a barrel, I would want to push the blast out away from me.

14 May 2010, 11:34
Stick, that may be the end route for this. I know that the very modest additional weight is really a non issue being right at the support hand, and outside of range, blast is a huge issue on pistol barreled rifles. I suppose I'm still trying to stay somewhat compact. The option of running a can is simply a luxury in my opinion, no where near 'mission required' for either upper build. I think it'll be a bit complex enough to tune this to 3 different rounds (90gr, 95gr, 110gr) without having the headache of adding a can, and still be able to have the BCM run when needed. Goal is to tune the lower/buffer to run optimally with both uppers.

I'm going to avoid the A2 style birdcages for blast reasons (VLTOR and others), and may simple try out Troy's claymore and Vortex. At least with the Vortex, I may be able to pawn it off on my old man for his M6A3 in 6.8. I know the 7.5 will have unburnt powder issues, but an attempt to reduce some signature would be nice.

Jerry R
14 May 2010, 12:42
At least with the Vortex, I may be able to pawn it off on my old man for his M6A3 in 6.8.

Hey, I resemble that remark !! Let's be a little careful tossing "old" around so freely! [:D]

14 May 2010, 18:55
I've seen the OPS M4-S used on a 7.5" (this is 5.56 mind you), but something that size in 6.8 might be worth considering. Lead time would be rough, as it's not out right now, but the M4-S compares favorably to the KX3, in spite of the $200 IRS donation and pesky mount.
I'm getting one to run on a 5.56 10.5" Upper, though your intended use probably differs from mine.
That said, a blackout or vortex should work fine to tame flash, but the KX3 is a better choice as far as direct blast away from you, and making it more shootable.

14 May 2010, 19:31
The M4-S is something I'm kicking around for the 11.5 upper in 5.56, but we're in the same line of thought. A plus to the pesky mount is the ability to move up to another OPS model later, should I choose to go that route.

I guess I'm seeing some experimentation going to happen with this. Should I end up using the KX3, I want it to be simply to direct blast, not to bandaid a potential reliabiity problem.

Hey, I resemble that remark !! Let's be a little careful tossing "old" around so freely!

Oh yeah, you're on this board. Um, scratch the old remark, I'll be needing to borrow that chrono for this.....[BD]

17 May 2010, 13:45
We make an 8.5" as well, you will not clear a 7" rail with the 7.5" barrel for mounting a can.

Besides the issue of no silencer manufacturers recommending/warrantying that short of a barrel people overlook the stress to the weapon. The 7.5" barrel with pistol gas will be overrun very hard with the additional pressure of the can.
I would expect bolt life to be shortened and possible extraction issues.

17 May 2010, 15:52
todd - I thought I had previously seen the 8.5" in 6.8 before on the site, then gone. Limited runs?

I've long given up the idea of running a silencer on this build for the 6.8, it was more of a creature comfort if it could have been done reliably. As it is, it would simply be a ridiculously unecessary expense (to me).

The more I talk about this build, the more impatient I'm getting during the stamp wait....

Thanks for the input on this!

19 May 2010, 10:55
We do a batch of 8.5" when we can.

20 May 2010, 18:35
Great, thanks todd. I'll be calling the shop with the last couple remaining questions before ordering.