I am currently in the process of procuring all of the necessary parts for a accuracy 5.56 build.  The next part on my radar for purchase is a stripped upper receiver.  After searching many websites, I don't feel like I am much closer to making a decision than I was when I first started looking.  I have decided to make this post for some recommendations to hopefully narrow my choices down.  About the only decision that I have made so far is that I think I want to go with a forged upper instead of a billet one because there doesn't seem to be any accuracy advantage of one over the other.  I had originally thought of going with a Spikes stripped upper to match the Spikes lower that I already have, but the responses to a post that I made a week or so ago seem to suggest that Spikes uppers don't seem to fit as tight together with a Spikes lowers as some of the other brands of uppers do.  So, I am back to square one and would like to get opinions on the perfect stripped forged upper that seems to be built to "a little higher quality and tighter tolerance" than the average upper and will offer the best chance of a successful accuracy build.  Thanks for all responses back.

No one is really able to accurately predict if any one upper is going to be a good/tight fit with any one lower when they are purchased separately.  Doesn't really matter who makes it, they all will have a specific tolerance range and there's no way to guarantee your upper and lower won't be on opposite ends of that spectrum.

There's a few ways to get around this.

-  Purchase your upper/lower as a "matched" set.  
-  Purchase a lower that features a nylon tipped "tension" screw.
-  Use one of the many stop-gap measures that are available to tighten your upper to lower fit (o-ring, accuwedge, etc.).

If you already have your lower in hand, it would seem option #3 is your only viable solution unless you luck out with whatever upper you decide on.  If it were me, I'd just pick up a quality forged upper and not worry about any of it.  Chances are you'll be fine.

While you'd think an upper has little to do with accuracy, I've seen quite a few billet uppers used on precision rigs.  This may be financial (they got the money) or it may have something to do with being more heavy/ rigid due to the upper design and extra material.

I recently picked up a CMT billet upper for my project, and several have recommended the VLTOR MUR and Mega billet uppers.

Seems like everyone has the same idea to build a tack driver (I blame LaRue for selling so many Stealth barrels) and the beefier billet uppers have been hard to find in stock.

I like the Vltor mur uppers, I prefer them over my Colt's honestly. Very rigid, fit tight on all my lowers, only downside is they are about the most expensive forged upper there is. Midway has them for around $160 now but there oos until next month.

Vltor MUR 1S for me..............

VLTOR, Mega and CMT uppers are desirable for accuracy builds but it also depends on the barrel extension. Hate to say but you don't know for certain until you try to mate them.


And a 9mm pistol caliber carbine. And a 308 build. And a 6.5 Creedmoor build. Quality uppers have been hard to find.

I wouldn't use forged for a precision build. All that truing up of the receiver face to mate with barrel extension can be avoided by a good CNC machined billet upper. Much more precise than the machining on a forged upper. Less risk.

None of my Aero forged uppers needed to be trued up.  I have other forged uppers that have, but Aero hasn't given me any issues.

The upper receiver isn't going to affect accuracy one way or the other if it is made to spec.  People put nice uppers on precision builds most likely because they've already dumped all that money in to it, why not add a little flare?

Billet uppers have more material because they are inherently weaker, not the other way around.  They aren't considered stronger because they use more material, they use more material because, all else equal, billet will be a weaker product than forged.  The extra material just makes up for the difference.

My Spikes forged upper seems to work well with my new Lilja barrel.  I did true the face of the upper before "marrying" it to the barrel extension and torquing the nut.  I find it a bit difficult to believe that a billet upper would improve accuracy.  I'm still trying to optimize the handload for 100 yards but am at this point in load development.  Its been too hot and humid to do much shooting here in South Mississippi, but I think I can get groups down to about .350" once the 90+ degree temps let up.  The limit will probably be me and not the rifle.