300 Blackout AR is making me crazy

[Elkins45]

My AR-15 10” SBR is one of the most infuriating guns I have ever owned. The flat top upper and bolt came from a ban-era Bushmaster, the stainless barrel from MidwayUSA (AR Stoner brand) and the hand guard is a free floated Brownell’s tube. I mounted a Leopold2x7 scope (used) on it. The gun is only intended to be used subsonic and suppressed.

To get it on paper at 50 yards I had to crank it to the extremes of adjustment in both windage and elevation. OK, so the upper must be bad...so I swapped in a new Aero Precision upper without a forward assist because I’m a lefty and don’t like having the FA to blow gas back in my face. Didn’t fix it, so I put on a 20MOA base and windage adjustable Weaver rings. Didn’t fix it, so I bought a brand new Leopold to replace the older one I had been using.

So I still have to crank the new scope all the way. I’m beginning to think the barrel has a warp or the extension isn’t square. So now I guess it’s time for a new barrel... This thing is becoming Theseus’ ship! Guess that’s what I get for starting with a Midway clearance barrel.

I hear good things about Faxon.

 

[FL-NC]

I was more interested in the round than the gun. Mine is a Ruger American ranch.

 

[clearcut]

Maybe try some iron sites ,bore site? As a test ,have you tried R n R the BBL.

CC

 

[Everready73]

Faxon are good as well as Ballistic Advantage. You can usually find good deals on Faxon and BA at AIM Surplus, Granite Ridge Outfitters, And Right To Bear Arms. Right to Bear has their house brand barrels which are BA and they are priced right

 

[RussellC]

I used an 80 dollar barrel from classic firearms and a 50 dollar Chinese red dot. Surprised me how accurate it was with my hand loads. Very odd the problem you are having, sounds indeed frustrating.

 

[Elkins45]

Faxon are good as well as Ballistic Advantage. You can usually find good deals on Faxon and BA at AIM Surplus, Granite Ridge Outfitters, And Right To Bear Arms. Right to Bear has their house brand barrels which are BA and they are priced right

Thanks for this. I will investigate...

 

[Elkins45]

Maybe try some iron sites ,bore site? As a test ,have you tried R n R the BBL.

CC

R n R?

 

[CarJunkieLS1]

I would try having the upper receiver lapped and then you can bed the barrel into the receiver. If that doesn't work you've got a tomato stake of a barrel.

 

[someguy2800]

Throw the barrel in the bin and move on

 

[easy]

Has the upper receiver been tried with a different barrel? Has the upper receiver been trued? One of those is your problem.

 

[Elkins45]

Has the upper receiver been tried with a different barrel? Has the upper receiver been trued? One of those is your problem.

The original upper came from a 223 rifle that didn’t have any issues. I’m really thinking it’s the barrel.

 

[clearcut]

R n R = remove and replace. If you can try an other barrel on your upper (I just read your last post) I think you are right its the barrel .I'll bet no return on clearance ,I'd give them a call and see if they will work with you .

CC

 

[IndianaBoy]

How tightly did the barrel fit into the upper? You may need to shim the barrel extension into the upper if tolerance stacking resulted in a sloppy/loose fit.

 

[Elkins45]

R n R = remove and replace. If you can try an other barrel on your upper (I just read your last post) I think you are right its the barrel .I'll bet no return on clearance ,I'd give them a call and see if they will work with you .

CC

It's four years old and I engraved my NFA information on it...although at one time Midway used to say they offered a lifetime warranty on everything they sold. Since that was back in the 90's I'm not sure that's the case anymore. Still, I think your suggestion is worth a shot. Midway has always been a good company to deal with from my past experiences.