reasons for accuracy issues?

[Dildobaggins]

So I finished my 6.5 Grendel Build. I went out to shoot it/ break it in. I put 100 rounds of hornady black 123gr ELD-M. it functioned flawlessly. I was actually quite proud of myself haha. Best I could get was a 5 shot group of about 2 MOA. Ive had several ARs, all of them shot well other than a ballistic advantage barrel. However this is my first full build. Ive triple checked everything as far as proper torque on barrel nut, and gasblock etc. Any suggestions would be helpful. Heres a quick rundown of what I have. I also understand that I have only put 1 type of ammo through it. I just cant believe Hornady shot that bad. Every single gun ive ever had, no exceptions Hornady has always shot excellent. Thanks

Odin works 18'' DMR barrel
Odin works adustable gas block
grendel hunter handguard
Aero receiver
Odin works BCG
80 percent lower
CMC drop in trigger 2.5 lbs
Nikon Prostaff 4-12 scope.

 

[natdscott]

Is the carrier floating?

Have you checked your mounts, made sure you pushed it/them forward to full engagement as you torqued it down?

Is it a proven scope? (ie: put it on something else and see)

 

[Dildobaggins]

Scope is proven. I took it off an ar that I shot a 2 months ago. Handguard is freefloat as well. Checked to make sure the gasblock was not touching the rail, and its clear.

 

[6.5SH]

Let someone else shoot it. If same results is likely the barrel.

FWIW most barrels that say "SAAMI chamber" aren't. A proper 6.5 Grendel SAAMI chamber includes the compound throat. Those will in general shoot any decent loading well. The ones with bastardized throats are a crap shoot. The only way you'll know is with a bore scope or casting the chamber.

 

[natdscott]

Scope is proven. I took it off an ar that I shot a 2 months ago. Handguard is freefloat as well. Checked to make sure the gasblock was not touching the rail, and its clear.

Carrier.

I asked you if the carrier floats, in battery.

 

[Dildobaggins]

Carrier.

I asked you if the carrier floats, in battery.

Sorry im still new to this. I'm not quite sure what you're asking. The carrier goes in and out of battery fine. Sorry for the hassle but could you explain what you mean?

 

[Dino11]

I would try some different ammo, Hornady Black from the factory does not shoot very well in my gun. But my home rolled Nosler 105 RDF's print sub MOA in the same gun. Even if I load my own Hornady 105's the Nosler bullet way out performs them.

May not be a fair comparison as I shoot a 6mm compared to your 6.5, just my findings on the Black line of ammo.