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Bought myself an aero precision upper...

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July 12, 2018, 02:07 AM
creslin
Bought myself an aero precision upper...
So a few months ago I bought this upper.

Slapped it onto a lower with a magpul PRS stock and a geissele trigger.
Put a nightforce scope and a saker suppressor on it and took it to the range for sight in.

Once I got on paper.. I discovered that I couldn't hit shit with it.
I was literally getting about 5 MOA groups with 77 grain sierra match king HPBT.
I'm not the best shot in the world.. but at 100 yards I can generally get within 1 MOA with a good rifle and good ammo.

So I got a little disgusted and simply put it away and shot other things.

Thought about it for a bit and decided maybe the suppressor was messing with me... so I took it off and went back to the range again!
Same ammo and everything.. same result.
My groups sucked.
Double-checked everything to make sure I didn't have loose scope rings or something silly.... everything was good to go.
(I have since re-appropriated that scope for my shiny new scar17 and it works great)

So I'm left sitting here with what "should" be a great precision AR.... but.. it's not.

Anyone have any thoughts of what I'm missing?

I had a coworker suggest I go dump about 100-200 rounds of non-match ammo through it to "break in the barrel".
Currently.. that's the best idea I have.





This is where my signature goes.
July 12, 2018, 06:23 AM
SgtGold
The barrel specs say it should shoot. Two things to check are gas tube float and gas block clearance under recoil. If the gas tube is pinched in any way, or if the gas block makes contact with the handguards the rifle will group like your's does. You might want to send it back and have it checked by the manufacturer.

Edited due to fat fingers.

This message has been edited. Last edited by: SgtGold,


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July 12, 2018, 08:51 AM
RHINOWSO
If you have gone down the rabbit hole of checking everything on your end, I suggest you contact AP.

I had a lower of theirs with a tight magwell (would only work with aluminum 30rds mags, every other mag wouldn’t fit or had to be ripped from the magwell) and they fixed it in short order.

That being said, AP woudn’t be my first choice for a precision AR build. I like my setup but it’s just a 16” midlenght I use soley for <50m training drills. But even then it shoots better than yours with Wolf 55gr (I can ring a 4” steel plate all day long with it).
July 12, 2018, 09:44 AM
fritz
I have no direct experience with Aero.

As others continue to state, check & double check for the obvious & not-so-obvious items.

- Loose scope mounts & scope that doesn't track. I had an accuracy and POI issue with a recently re-barreled upper. Scope and mounts were my first thoughts, but switching multiple scopes across multiple uppers eliminated glass as a problem.
- Gas block to rail clearance can be an issue. It was in my case, but it wasn't the root problem.
- Ultimately my problem appears to be a slightly loose barrel nut. My 'smith tightened it and milled away a bit of the gas block. First time out, after some 150 rounds, so far so good. My 'smith said the adjustments he did were very minor.

These issues apply only to my upper, but it means that a number of items should be checked first.

And then there's ammo. A true 1/7 twist should stabilize 77 SMK bullets. But try other ammo. I have yet to own an AR-15 barrel that didn't shoot Hornady 55 Vmax and Federal 69 GMM well. Barrel lengths of 14" to 24", twists between 1/9 and 1/7, 223 and 5.56 chambers, barrel brands, with or without muzzle devices. Some barrels just don't mix well with some types of ammo. I'm finding that the Hornady 73 ELD that shoots so ludicrously well in my tight chambered Krieger barrel, can be either just OK or pretty bad in Wilson 5.56 barrels.

It appears you have a melonite barrel. I've heard they take a little longer to break in. But if accuracy is your goal, they use good ammo to put some mileage on it. During that time you should be able to determine ammo types work better than others.

And of course, have someone else shoot your gun.
July 12, 2018, 06:54 PM
smschulz
Like mentioned above:
* Try different and varying ammo
* Try without the suppressor
* Could just be a shitty barrel.
* Double check your optics

Most all of mine are SS Wylde and all great shooters (sub MOA).
The ones with standard 556 are substantially less accurate.
July 12, 2018, 08:53 PM
jjvgnslngr
There are only 2 reviews on that upper, but they both mention sub-par accuracy.


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