6.5 Grendel

[Critter Picker]

What type of magazine are you using? I've been told to use ARStoner mags, feeds slick as snot on a doorknob. Everybody told me that the Grendel is really finicky so I have the metal mags.

 

[Shane Lindsey]

What type of magazine are you using? I've been told to use ARStoner mags, feeds slick as snot on a doorknob. Everybody told me that the Grendel is really finicky so I have the metal mags.

Using the Duramag (28) I think.

Tested each mag with single sbot to see if they functioned and locked back. Each worked fine. The tested with multiple rounds and found one that functioned less reliably.

 

[Shane Lindsey]

Will pull the scope and test it on a shooter to make sure that is not issue.

Test different ammo.

If that fails, I think it is a barrel issue.

 

[Shane Lindsey]

Good.
Perhaps just slightly low enough on pressure to not lock back.
Could still be a slight gas issue.
Could be slightly tight lug to battery...enough to drag a teeny bit.

Are you using an H buffer or standard carbine buffer and spring? This will make a difference on lock back and/or picking up the next round as well.

Either way...Accuracy shouldn't be as bad as you are seeing.

Not sure on the buffer. Using a lower from a Springfield Saint 16" I had. (New to ARs, shot my buddies Grendel a few weeks ago
and decided to order one).

 

[Shane Lindsey]

Well cleaned the barrel today. It cleaned up pretty easy with BTE. I did notice it felt a little rough in spots. At least when the patch was wet. As I dried it out, they felt smoother. We shall see.

 

[Shane Lindsey]

Good.
Perhaps just slightly low enough on pressure to not lock back.
Could still be a slight gas issue.
Could be slightly tight lug to battery...enough to drag a teeny bit.

Are you using an H buffer or standard carbine buffer and spring? This will make a difference on lock back and/or picking up the next round as well.

Either way...Accuracy shouldn't be as bad as you are seeing.

Carbine buffer. Weighed 3.9oz last night. Looking at a few sites that sell them, this seems really light???

 

[Roughrice]

The use of carbine buffer is fine.
You should get maximum bolt blow back with it.
Only if it's acting over gassed would you need an H buffer or adjustable gas block.
Surprisingly though, you said you used 123 grain and still not enough to lock back on empty mag.
That usually points to a problem somewhere else… like gas restriction or bolt drag.

 

[Shane Lindsey]

It would lock back, but consistently/reliably.

 

[Roughrice]

May just need some cycling/ break in.
Lube it up and work the **** out of it.
Hopefully your accuracy is there.

 

[Shane Lindsey]

Youtubed the snot out of some AD mounting. Going to try something a little different and see it I had the scope all jacked. I have seen bad rings do funny things...fingers crossed.

 

[Turpentine21]

Interested in how this comes out. Sounds like an issue with the barrel for sure if your scope checks out. I have been using 10 and 20 round DuraMags and they have been very good. I do adjust the feed lips slightly on every mag I get.
I mounted my AGM Adder in American Defense mounts. They have been rock solid. But, they do not return to dead zero if I remove from the rifle and then reattach. They will be close but have been up to 3moa off. I get much better repeatability with one piece mounts and a good Torque driver.