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The 6.5 bug hit me and I decided to order an upper...Really liked the looks of the Aero with their new handguard. Picked up the Vortex Razor HD LH in 2-10 with an Aero Mount. Also ordered some Wolf FMJ and Hornady 123 SST's to go along with it. Put on top of an Aero lower with PSA EPT.
Cleaned the upper good, lubed, ready to go - Using Elander 17 rd. magazines. First 3 magazines ran like butter. I was getting approx. 2 to 2.5 MOA (shooting at 100 yds) so was pretty pleased initially given the ammo using.
Decided to try the SST's - Could not get better than 3 and up to 4 MOA using them. To say my bubble was busted is an understatement...very surprised.
Went back to Wolf - still 2-2.5 MOA.
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Welcome to the forum jbd,
The Hornady 123 sst custom load is a finicky load, for some reason it only likes a few barrels.
For factory I'd say try the Hornady 123 Black (eldm), there are also a couple other mfrs but this one I know.
A lighter one is the Federal AE 90 gr TNT, also good for varmints.
Also for a lot of barrels there needs to be a break in of somewhere north of 50 rounds before you should start expecting good groups (some barrels of course will group sooner).
Wolf is an undersized bullet diameter so most guys see only 1.5-2.5-3 moa.
I don't know that trigger but many times you can improve your shot groups by a better trigger. Lots of guys have gone for and praised the Larue MBT-2S, pretty good deal. I have mostly timney or timney-like single stage, 2.5-3 lb triggers and they have helped me.
There is also some getting-used-to shooting an AR... esp when it's a bit harder of recoil than the 223's. But still very mild, just getting more and more time behind the trigger will help you.
"Down the floor, out the door, Go Brandon Go!!!!!"
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I can’t explain it but recent lots of Hornady 123 grain SST accuracy hasn’t been as good as prior to the release of the ELD-M 123 grain ammo. I got a PSA EPT trigger with my 6.5 Grendel pistol kit but I swapped it out. I’m spoiled from using good two stage triggers and I really like the MBT. I just bought another LaRue MBT 2S trigger on sale for $80 and two more 17 round E-Lander mags.
Sounds like you got a very good 16” 6.5 Grendel I hope you enjoy it.
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Thanks for feedback. Not new to AR platform - Just new to Grendel. I am going to order some 123 Black's and see how they do...I could pull an MBT out of one of my others to see if it helps. Don't think trigger was making that much of a difference...Like I posted, I was getting 2MOA with Wolf which seems to be pretty satisfactory from what I am reading on the forum.
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Welcome JBD,
My story is about the same. 20" Odin stainless barrel. Out to 900 yards the 123gr ELD factory shoots as good as anything. The factory 123gr SST's ran a full 2 MOA. Not really that bad but almost twice the group of the ELD's. However.... The 123gr SST's in reloads with 8208 powder shoot right up with the ELD's.
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jbdial1515 Wrote:Thanks for feedback. Not new to AR platform - Just new to Grendel. I am going to order some 123 Black's and see how they do...I could pull an MBT out of one of my others to see if it helps. Don't think trigger was making that much of a difference...Like I posted, I was getting 2MOA with Wolf which seems to be pretty satisfactory from what I am reading on the forum.
Welcome too the horde sir.
I will echo what the others have said, shoot the sst ammo and safe the brass, hornady sst ammo has gone down the drain.
I would try some eld-m ammo and some federal tnt or federal 130 otm.
Barrel might need a few more rounds too break in, also I would upgrade the trigger as well.
Never hurts to double check you scope and scope mounts.
Me personally. I would break the gun open lap and bed the barrel and remove the muzzle device and throw the crush washer in the trash. Get some accuwashers and time the muzzle device so it's true without any torque and use red locktite to secure it.
Google balanced torque theory, it will help you understand what I'm talking about with the barrel nut and muzzle device torque throwing off groups.
Hope this helps sir.
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I've been thinking about the muzzle device and crush washers, I think I have an idea why this might be so...
The issue, mechanically, with a crush washer is as you tighten it, it goes off-center-bore due to the semi-conical shape of it.
An accuwasher OTOH, or use of a jam nut, allows use of symmetrical flat mating surfaces so the device (whatever you have) will have more probability of being center-bore and evenly torqued, thus not throwing off the bullet path as much. May not be much but it certainly could skew the forces around the bullet when exiting the barrel. Have to confess this took me a while to figure something out, but this is a theory that makes sense to me.
"Down the floor, out the door, Go Brandon Go!!!!!"
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grayfox Wrote:I've been thinking about the muzzle device and crush washers, I think I have an idea why this might be so...
The issue, mechanically, with a crush washer is as you tighten it, it goes off-center-bore due to the semi-conical shape of it.
An accuwasher OTOH, or use of a jam nut, allows use of symmetrical flat mating surfaces so the device (whatever you have) will have more probability of being center-bore and evenly torqued, thus not throwing off the bullet path as much. May not be much but it certainly could skew the forces around the bullet when exiting the barrel. Have to confess this took me a while to figure something out, but this is a theory that makes sense to me.
You might be on to something gray.
My understanding of it is that the torque value can effect harmonics are barrel whip if you want to call it that.
Ofcourse if you start off with a barrel that's a turd, no matter what you do it will probably always be a turd. Not saying that's what the OP has going.
Just that you can put lipstick on a pig but it's still a pig.
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Diamondback firearms 18” Grendel barrels shoot SST into an 1”
$129
I’ve shot 5 of their barrels and they’re consistent
Just in case you’re not happy with the Hornady Black groupings...
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grayfox Wrote:I've been thinking about the muzzle device and crush washers, I think I have an idea why this might be so...
The issue, mechanically, with a crush washer is as you tighten it, it goes off-center-bore due to the semi-conical shape of it.
An accuwasher OTOH, or use of a jam nut, allows use of symmetrical flat mating surfaces so the device (whatever you have) will have more probability of being center-bore and evenly torqued, thus not throwing off the bullet path as much. May not be much but it certainly could skew the forces around the bullet when exiting the barrel. Have to confess this took me a while to figure something out, but this is a theory that makes sense to me.
Im a fan of Smith vortex flash hiders. No washers at all. No torque at all. Hand tighten no lock tight at all. The gases flow in the proper direction by the twisted prongs to keep the device screwing down with every shot.
