Hello.

Sounds about normal really. Noveske barrels are very accurate. You may just have to find a load that the other barrel likes. M855 isn't known for accuracy.

I was very impressed with Noveske for sure. m855 with penny size group . but the other one seemed shooting backwards

 

Could have been anything. Some 1:9 barrels just like 55 grain stuff more.

Try running some 55gr through the 1/9 and see if that makes a difference.

Thank you guys. I will try 193 then.

 

You should be shooting 55grn through the 1:9 for best results.

Your Noveske barrel will be more accurate than the other barrel. Do a google search on Noveske barrels, there is an interview with John Noveske from about 5 years ago by David Crane I think and he discusses how the barrels are made and why they are awesome. Good stuff.

Yes, all else being equal, a non-chromed barrel will be more accurate than a chromed barrel. But your 1/9 barrel is not equal to the Noveske barrel.

My 1/9 is considerably more  accurate with 62 grain 855 than 55 grain 193.   just saying.

Cheap barrel from SG isnt as accurate as noveske? And? Sounds pretty normal to me too...

A shooter that can tell the difference in accuracy between a chrome lined and non-lined barrel can zap gnats at 1,000 yards.  

Today's chrome lining processes are several orders of magnitude better (and more precise) than when the gun shop lore of "chrome lined barrels aren't accurate" got started.  

No, "unlimited-class" benchrest shooters don't use chrome lined barrels.  They use stainless steel barrels that were made by hand, by craftsmen who hand-lap the barrel and obsess about the polish on the crown.  And these barrels are "shot out" after maybe 1,000 rounds, because the competitor will feel that they aren't as "gnat's eye" accurate after that.  

A combat rifle needs to be able to group at about 4MOA out to the effective range of the barrel/round combination, and modern chrome lined barrels will do that until they've had tens of thousands of rounds through them.  A civilian's rifle with a chrome lined chamber and bore will stay very accurate, assuming it was made with quality parts and built correctly, and be at least as accurate as the ammo the shooter uses in it (and probably more accurate than the shooter) throughout it's life.

And don't let the discussion about "1/9 needs 55 grain bullets but 1/7 won't shoot them well" confuse you.  Both twists will more than adequately stabilize all common .224" diameter bullets.  If you shoot ultra-light "varmint-bomb" type bullets loaded to very high velocities, you might have problems with either of these spins being too fast for those fragile bullets - just don't try to send that type of bullet out the bore at 4,000FPS, and you won't have problems because of the rifling rate.

From the Ammo FAQ:


WHAT BULLET WEIGHT CAN I SHOOT IN MY <1/9, 1/8, 1/7, etc.> RIFLE?

This is undoubtedly one of the questions that is asked the most. The answer depends on many things, but here are some rough guidelines for those that don't care about the details:
1-in-14" - 55gr or less
1-in-12" - 35gr up to 55-60gr
1-in-9" - 45gr-75gr, possibly up to 77 if you're lucky
1-in-8", 1-in-7" - 45gr - 80+gr

To find out for sure if your bullet will stabilize a given bullet which is on the fringe, you'll have to try it out in YOUR rifle. Some people's 1/9 can't stabilize 75gr bullets, while others can get away with 77gr bullets in theirs. Technically, it isn't about the WEIGHT, but the LENGTH of the bullet, as well as air density and velocity. A simplified method for determining the minimum rifling twist rate for a given length of bullet is given by the Greenhill formula. A Google search will show many sources for those interested in a more in-depth discussion. If you have the length of your bullet, and just want a look-up table to see what twist rate you need, refer to this page. If you really enjoy the in-depth mathematical treatment of the subject, check out these pages .

This is simply untrue.  In my experience, a chrome lined bore, such as the Noveske I recently sold after a few thousand rounds, is going to be about half as accurate (double the group size) as a similar stainless or otherwise unlined barrel.  In fact, I have two stainless barrels with the exact same profile as the Noveske, made in the same FN manufacturing plant, and I can print groups half the size that the Noveske with chrome lining would print.  Roughly 0.75 MOA vs 1.5 MOA on average.  At 100 yards it's noticeable.  At 400 yards, it could be the difference between making a precise shot, or not.

Noveske's stainless barrels are even slightly more accurate than the lighter profile FN stainless barrels mentioned, verging on 0.5 MOA accuracy.

Not all rifles like all loads. I'm sure if you try enough combos you'll find a load it likes.

I recently shot my nitrided 14.5 arfcom upper, its a 1/9 twist. at 50 yds I got 15 shots in a 1.75" diameter with 55 grain using my primary arms M4 red dot. 75 grain was more like 3-4" but it was also 40 degrees and windy. My 1/7 twist LMT likes the 75 grain better, like people say every barrel is different. Has anyone else shot one of those arfcom uppers or were people just buying them to flip em.

My LW 1:9 barrel shoots M193 and M855 about the same (2 MOA.)  It will shoot 75gr. BTHP Match ammo quite nicely (1 MOA.)
My Spikes 1:7 barrel can't shoot M855 worth a crap, but is a razor with the Match loads.
8 MOA out of your 1:9 barrel seems really odd, OP.  Maybe the barrel nut is loose, or the crown is damaged?



Were you using irons?  If not, check that the optics mount is not loose, or that the optic itself is a not a problem.



 

greenhill formula Twist=150(d/r)

Twist =150  (diameter of bullet/(bullet length divided by its diameter))   use 180 for greater than 2800fps  Then round it to the closest twist rate available in your barrel.

This may help

Not to mention if you were experiencing accuracy problems as a result of improper stabilization I think you would be experiencing a keyhole or two.  I could be wrong but just my thoughts on the matter.

You just described two great examples of the "some barrels like some loads but don't like some others" syndrome, which may be what the OP is experiencing (though to an extreme degree).

It seems twist rate and barrel preference will change the ballistic dynamics.

try some SIERRA SMK or Hornady VMAX loads.

M193 and M855 are not know for accuracy

Noveski makes great barrels

I have COLT, SABRE and DANIEL chrome 1:7 barrels, and all three shoot quality 55gr VERY well.

Then don't bother to post - Eric802

Didn't even bother to read the thread, didn't have to.


ETA: sorry for being so short, but all of this 1/7 vs 1/9 is just about silly especially with 55 grain ammo.

have you considered shooter error?  are you consistently shooting the same groupings with each gun?  Also, why are you doing testing at only 25 yards? 100 yards is going to tell you much more in my opinion, get a bench and vise, do some shooting and report back

Yes I do believe in shooter's error. So I used leadsled DFT and geissele trigger. Though, I used 1x RDS M4s and 25 yard was only option for me that time.

Yep. It's a phenomenon that the AR crowd (generally speaking) never seems to have caught on to this - expecting a 1/X barrel to shoot X bullet best - while most bolt action guys, even the hunters not the precision crowd, tend to know you gotta find the load a specific barrel likes.

he difference has in my 20+ years of experience of shooting AR15s is that the difference in a 1/7 and a 1/9 only starts to make a difference around the 77 grain weight.
When I was shooting High Power I had a Kreiger barrel that was the most accurate barrel I have ever owned. It was a 1/7.75 and it would put 45grain JHPs in a ragged hole,
much like the 77 grains.

So a 55 grain bullet will shoot the same in a 1/7 as a 1/9 IMHO.

try real shots at  300m    get a better feel.. 25 meters  with an ar could be done from the hip. with any round

In a previous career, hitting in the black at 400 meters with a M4 and the M855 was no problem. Of my civvie ARs, the 1:7 barrels generally like the heavier bullets, though ammo type/manufacturer varies between each, some not significantly, and with a couple, more so. I think with any long gun, finding the best type/manufacturer or reload that your particular gun shoots the most accurately given your needs and conditions is to be expected.
Good thread with good feedback.

Pretty much everything has been talked about, but what kind of targets were you shooting at? How precise of a point of aim spot? 1" vis dots, 10" circles with bulls-eye? I've seen some people open up groups primarily because the target didn't have a definitive aiming point, IE 4" solid black circle ect.

Captain Obvious here with today's common sense:

Some barrels like different bullet weights more than others and shoot better or worse with specific loads.
Just because you paid more for a "premium" barrel doesn't necessarily mean it will shoot all ammo better than a cheap barrel.

Mind = blown