Have heard this mentioned offhand a couple of times around the web and was curious if the brain trust here at M4C could speak to it.
Does running a thicker-walled billet upper really have an appreciable effect on accuracy on an AR-15 chambered for .223 (or, for the sake of argument 6.5G)?
If so, how much? Is this something worth upgrading into, or is that money better spent on higher-quality glass?
It would be better spent elsewhere IMO.
I built many precision uppers with standard, thick billets, and forged VLTOR MURs and cannot tell any difference.
The two most accurate uppers I’ve assembled to date (n ~ 40 or so) employed a heavy billet vs. a blemished BCM (!), but both have Krieger barrels. Having mentioned that, I’ve used Douglas, Krieger, Critereon and WOA barrels on uppers that didn’t seem to be shooting to their potential. The solution was swapping upper receivers and using good handguards with the correct torque on barrel nuts. I now have a very strong preference for handguards that uilize barrel nuts that do not require gas tube alignment such as the KMRs and Geisseles.
What’s most important is getting and upper that’s in spec.
I believe the proper application for the heavy walled upper receivers is when you are going with a long heavy barrel. Don’t believe the m-16 was designed for 26" 5# barrels hanging off the front.
they sure do shoot good though. Just don’t want to have to carry it too far.
Good point that I neglected to mention. IF you’re using a long, heavy barrel it wouldn’t hurt to opt for the thick-walled upper.
I’m assuming the RIS II family of rails would also fall in this category?
personally I like the PRI forearms. not really a fan of rails. I use the PRI delta. Nice flat bottom for shooting off a rest. the PRI is very secure when installed.
As far as timing the barrel nut with the gas tube. It is no problem for me. I can pretty much establish whatever barrel torque I want. The AR’s I build are all precision. I want a barrel nut torque around 35 or 40 pounds. I always lap the face of the receiver anyway. It is a simple task to lap and test your barrel torque until you have the gas tube alignment and torque you are looking for.
different strokes for different folks
I have one of nearly every variant of the Vltor MUR upper, and those things are excellent. My most accurate upper is a Centurion complete unit with a plain forged upper, but a really nice Mk12 barrel.
To say that the upper isn’t going to provide accuracy gains is pretty much established. The MUR looks good, is fairly easy to deal with, and the upper/handguard fitment is truly exceptional, but even I classify going with those uppers are more show than go.
Better ammunition, better glass, better trigger, better barrel in that order in terms of cost -> ROI. Better ammo is cheap performance, the next two are all about minimizing introduction of human error into the accuracy equation, then a better barrel/muzzle device/suppressor can be the best approach to extract more accuracy.
opinions vary
a 2.5# barrel vs a 5.5# barrel
I just wish MURs worked with foldable offset sights. That’s really annoying me right now, to the point that I’m considering selling my 16" Noveske Recon upper and building one with a standard upper and KMR or Geissele rail.
what the hell do you need with foldable offset sights.
What is your definition of accuracy?
can you put five 1/2" five shot groups on this target?
Because a magnified optic makes it hard to use regular BUIS and I prefer to have them folding so they’re out of the way when they aren’t needed.
I’ve had the same issue - I’m able to run the rear off the handguard with the big apeture only, but it’s not the most ideal feeling. It worked well enough I decided to pick up a second set of KAC offsets after getting that ironed out, but I agree it’s a big issues with the MUR-1A
My definition of accuracy is real-world 6" diameter 10-shot groups at 400m from anything supported for most applications - I figure I’m good enough to do that with a 3/4MOA rifle/ammunition pairing in anything that doesn’t qualify as ‘windy - gusty’ from supported. I realize this isn’t amazing for the internet, but I’m not that gifted a precision shooter, but I know I can shoot very well within some disciplines (4x Expert w/ M16, despite being seriously awful at 200 standing - as soon as I got a TA31RCO it was possibles on both Table1 rapid fires and minimum 97 Table 2/3 shoots from there) - with fantastic equipment and ideal conditions I’m sure I could do 3/4MOA, open that up two-fold and I’m at my aforementioned accuracy target.
Offset irons make sense because one can’t cowitness the irons with a zoom optic or low powered variable. Not ideal for shooting with irons, but far better than the next best thing for most applications.
That’s a hell of a challenge for most who say their ARs shoot .5 MOA. I’ll admit that I can’t with any of my best ARs- at least not consistently. I might pull a ringer target, but that would not be the norm. I can do five 3/4" MOA groups, but even then I might screw the pooch on one group.
This is typical and is recent:
My bolt guns are better.
now that is damn good shooting. My opinion if you can shoot those 5 five shot groups and average under 1 moa you are doing great. I am impressed.
I have been trying for over a year now off and on and I still haven’t been able to do it. Always that flyer or your concentration goes or something happens. Fun trying though.
I just get tired of hearing about all these 1/2" and 1/4" AR’s. Show me you can do it consistently. Shooting a .375 group last year doesn’t cut it. Can you expect you rifle to shoot a half inch group on any given day?
bolt guns don’t count. Hell a good bench rest .22 rimfire will outshoot 95% of AR’s at 100 yards as long as there is no wind.
It’s always fun seeing people with no idea how to shoot. That’s one of the scary things about public ranges… having trouble keeping all the shots on paper at 100yd supported for example.
In my experience most rifles outshoot most people, but there are a significant number of people who can shoot (just not as many as can’t).
my rifles can outshoot me.
At my last gun range I used to help the range master put together target stands. Typical 1x2 uprights 18" apart in a 2x4 base. never could understand why the shooters were always hitting those uprights. you have to be really bad to miss the bull at 100 yrds by nearly a foot.
I have a buddy who loves the old mosins. he can just about beat anyone at the range with iron sights.
then you have the guy that shows up with his combat vest with clips hanging all off it and leg holster with a $3000 ar tricked out with all the options like he was in Afganistan.
public range is almost as much fun as the boat ramp follies on a holiday weekend.
Thanks. It certainly doesn’t come easy and those flyers are hard to figure out. I’m still unsure if it’s the nature of these rifles or the difficulty in shooting them as my bolt guns don’t exhibit these variations.
Funny you mention the .22 as I’ve a stock $360 CZ 452 with a cheap optic that will out shoot most of my ARs absent wind. Best bang for the buck IMO regarding precision shooting and discipline, but there’s only a little carryover to the AR platform.
Because they’re not doing it at 25 yds or using a boresighter for a new optic installation. Many new shooters slap on a new scope, then wonder why they’re not on paper at 100 yds.