What are the differences between various CHF barrels on the market?

[Molon]

Accuracy Evaluation of a Noveske 16” N4 Light Barrel







I’ve posted short reviews of Noveske N4 Light barrels in the past, so for this article we’re going to take a more in-depth look at the Noveske 16” N4 Light barrel. For starters, Noveske’s nomenclature of “Light” for this barrel is somewhat misleading/confusing. When most shooters hear the term “light- weight” in regard to AR-15 barrels, they think of the “pencil” barrel profile of the original Colt M16/M16A1 and also the same light-weight profile of the Colt 16” carbine barrel found on the Colt 6520 and 6720. However, this is not the profile of the Noveske N4 Light barrel.


Colt M16/M16A1 barrel . . .





Colt 6520 16” light-weight barrel . . .





The stripped-weight (no flash hider, no front sight base/gas block, just the barrel and barrel extension) of the Colt 16” light-weight barrel is 1 pound, 6 ounces. The stripped-weight of the Noveske 16” N4 Light barrel is 1 pound, 12 ounces; which is the same stripped-weight of the Colt 16” government profile barrel found on the ubiquitous Colt 6920.


Colt 6920 government profile barrel . . .





Noveske 16” N4 Light barrel . . .





As you can see in the pics above, for the N4 Light barrel, Noveske has done away with the next-to-useless M203 (grenade launcher) cut-out found on the Colt government profile barrel. The N4 profile also has a more evenly distributed barrel diameter (and thus weight) fore and aft of the gas block journal, which moves the center of gravity of the barrel farther aft compared to a government profile barrel. This all makes for a superbly handling 16” barrel.

The reason that Noveske uses the “Light” nomenclature for their N4 barrels is simply because the N4 barrels are lighter than Noveske’s original medium contour stainless steel barrels. For comparison, the Noveske 16” medium contour Recon barrel has a stripped-weight of 2 pounds, 2 ounces and as mentioned above, the 16” N4 Light barrel has a stripped-weight of 1 pound, 12 ounces.


The Noveske 16” Recon barrel . . .





The Noveske 16” N4 Light barrel is a cold hammer forged barrel. It has a mid-length gas system, “M4” feed-ramps and a chrome-lined chamber and bore. The barrel has a 5.56mm NATO chamber and a 1:7” twist and has been high-pressure/magnetic particle tested; as the barrel stamp indicates. Contrary to erroneous Internet reports, the N4 barrel does not have polygonal rifling.


The barrel stamp . . .






The mid-length gas system . . .





I conducted an accuracy (technically, precision) evaluation of the Noveske 16” N4 Light barrel following my usual protocol. This accuracy evaluation used statistically significant shot-group sizes and every single shot in a fired group was included in the measurements. There was absolutely no use of any group reduction techniques (e.g. fliers, target movement, Butterfly Shots).

The shooting set-up will be described in detail below. As many of the significant variables as was practicable were controlled for. Pictures of shot-groups are posted for documentation.

All shooting was conducted from a concrete bench-rest from a distance of 100 yards (confirmed with a laser rangefinder.) The Noveske 16” N4 Light barrel used in this evaluation was free-floated during testing using a Larue Tactical free-float railed handguard. The free-float handguard of the rifle rested in a Sinclair Windage Benchrest, while the stock of the rifle rested in a Protektor bunny-ear rear bag. Sighting was accomplished via a Leupold VARI-X III set at 25X magnification and adjusted to be parallax-free at 100 yards. A mirage shade was attached to the objective-bell of the scope. Wind conditions on the shooting range were continuously monitored using a Wind Probe. The set-up was very similar to that pictured below.














For this evaluation, I used one of my standard match-grade hand-loads topped with Sierra 55 grain BlitzKings. When fired from my Krieger barreled AR-15s, this load has produced ½ MOA 10-shot groups at 100 yards.










Three, 10-shot groups were fired in a row from the Noveske 16” N4 Light barrel from a distance of 100 yards with the resulting extreme spreads:

1.29”
1.18”
1.31”

for a 10-shot group average extreme spread of 1.26”. The three, 10-shot groups were over-layed on each other using RSI Shooting Lab to form a 30-shot composite group. The mean radius of the 30-shot composite group was 0.37”.

After firing the above three groups, I fired an additional five,10-shot groups in a row for a total of eight, 10-shot groups fired in a row. The average extreme spread for all eight of the 10-shot groups was 1.24”. I over-layed all eight of the 10-shot groups on each other using RSI Shooting Lab to form an 80-shot composite group. The mean radius for the 80-shot composite group was 0.39”.





The smallest 10-shot group . . .














The 80-shot composite group . . .






…..

[Molon]

Noveske 14.5” “Skinny” Barrel




The Novekse 14.5” “Skinny” barrel was tested while wearing a Centurion free-float rail. For this barrel, I fired eight 10-shot groups in a row from the bench at a distance of 100 yards using match-grade hand-loads. The extreme spreads for those eight groups were as follows:

1.78”
1.89”
1.68”
1.71”
1.81”
2.12”
1.60”
1.84”

For an average extreme spread of 1.8” and a composite mean radius of 0.55”.




…..

Accuracy Evaluation of a Colt 16" Light-weight Barrel


I conducted an accuracy evaluation of a 16” Colt light-weight barrel from a distance of 100 yards with the results shown below. The Colt light-weight barrel has a barrel diameter of 0.625” at the gas block and approximately 0.57” forward of the gas block. The barrel profile has a slight taper underneath the handguards from the chamber to the gas block with an average diameter of approximately 0.64”. The stripped light-weight barrel weighs approximately 1 pound, 6 ounces.

The light-weight barrel is chrome lined, has a NATO chamber and a 1:7” twist. This barrel employs a carbine gas system and has M4 feedramps. This is the barrel traditionally found on the Colt model 6520 and now the Colt model 6720. This accuracy evaluation was performed with a LaRue Tactical free-float handguard installed.

Colt 6520





Colt 6520 converted to a flat-top with a Colt M4 upper receiver





Carbine gas system





The barrel stamp.





M4 feed ramps






The stripped light-weight barrel weighs approximately 1 pound, 6 ounces.






The test vehicle.




Shooting was conducted from a concrete bench-rest using a Sinclair Windage Bench Rest in front and a Protektor bunny-ear bag under the stock. The ammunition used; match-grade hand-loads topped with Sierra 55 grain BlitzKings. Sighting was performed using a Leupold VAR-X III with a mirage shade. Magnification was set at 25X and the scope was adjusted to be parallax free at 100 yards. Wind conditions were monitored using a Wind probe.

Six 10-shot groups were fired in a row in a slow and steady manner. Those groups had extreme spreads of:

1.18”
1.92”
1.28”
2.53”
0.96”
2.24”

for an average extreme spread of 1.69”. Using RSI Shooting Lab, I over-layed all six groups on each other to form a 60-shot composite group. The composite group had a mean radius of 0.56”.






The smallest 10-shot group.















…..

[bigfeetz]

That is not what was posted. Here is the actual quote:

"I just recently purchased twenty of the complete PSA 12.5" and 10.5" uppers to test them out. So far they have functioned properly like the Daniel Defense and LMT's and have had zero issues. They don't have a huge amount of rounds through them but no issues of jamming have been reported."

He also made absolutely no mention of the difference in accuracy between those different brands of barrels.

I personally rented/fired one of the full-auto "M4"s at that business and probably 1/3 of the rounds that I fired key-holed badly, at just 10 yards.



....

Molon , you are quite knowledgeable about AR15's but do you think there is a possibility that the post you quoted is not the only one I was referring to? Here that same person refers to the post you picked as my sole source.

I started a thread about our experiences with M4 and that includes the PSA uppers. We've had zero issues with them. The units that we are using are the CHF units made under contract from FN. Some of ours getting close to the 15,000 round mark and again, no issues at all.

These are in our secondary vault and will slowly rotated into the everyday range inventory. We will be ordering another twenty units when we catch up on other platforms. They are all select-fire weapons with PSA uppers in 12" or 10.5" and function flawlessly with H-buffers.

So yeah, he did say that, part in your post and part in mine. I fully agree with him being the owner of both 10.3 DD MK18 upper and a 10.5" PSA CHF upper and they both group fine. Only difference is that the PSA barrel is less gassy with .070 gasport compared to the DD barrels .085 gasport. The DD BCG has a better finish and the staking looks cleaner.

I highly doubt that the full-auto M4's he puts out on the line are going to have his best barrels. If I were him I would also use barely serviceable barrels for people to finish burning out since they wont be trying for groups while rockin at full tilt.

Great post up above this one, very informative.

[Metric Matt]

Barrel Profiles




Colt 6520








Novekse “Skinny”








Centurion Arms “light weight”








Colt 6920








Bravo Company BFH









Noveske N4










Colt 6721





….




Accuracy Evaluation of a Bravo Company 14.5” Barrel






The focus of this article is the cold hammer forged (BFH) version of Bravo Company’s 14.5” barrel with a mid-length gas system. As can be seen in the pic above, this barrel has a government profile. This is a chrome-lined, NATO chambered barrel with a 1:7” twist. Bravo Company states that these barrels have been high-pressure/magnetic particle tested according to the current mil-spec.

I conducted an accuracy (technically, precision) evaluation of the Bravo Company 14.5” BFH mid-length barrel following my usual protocol. This accuracy evaluation used statistically significant shot-group sizes and every single shot in a fired group was included in the measurements. There was absolutely no use of any Group Reduction Techniques (e.g. fliers, target movement, Butterfly Shots).

The shooting set-up will be described in detail below. As many of the significant variables as was practicable were controlled for. Pictures of shot-groups are posted for documentation.

All shooting was conducted from a concrete bench-rest from a distance of 100 yards (confirmed with a laser rangefinder.) The Bravo Company 14.5” barrel used in this evaluation was free-floated during testing using a Daniel Defense Omega free-float railed handguard. The free-float handguard of the rifle rested in a Sinclair Windage Benchrest, while the stock of the rifle rested in a Protektor bunny-ear rear bag. Sighting was accomplished via a Leupold VARI-X III set at 25X magnification and adjusted to be parallax-free at 100 yards. A mirage shade was attached to the objective-bell of the scope. Wind conditions on the shooting range were continuously monitored using a Wind Probe. The set-up was very similar to that pictured below.












For this evaluation, I used one of my standard match-grade hand-loads topped with Sierra 55 grain BlitzKings. When fired from my Krieger barreled AR-15s, this load has produced ½ MOA 10-shot groups at 100 yards.











Three, 10-shot groups were fired in a row from the Bravo Company 14.5” barrel from a distance of 100 yards with the resulting extreme spreads:

1.58”
1.96”
1.50”

for an average 10-shot group extreme spread of 1.68”. The three, 10-shot groups were over-layed on each other using RSI Shooting Lab to form a 30-shot composite group. The mean radius of the 30-shot composite group was 0.49”



The smallest 10-shot group . . .






The 30-shot composite group . . .





….




Noveske 14.5” N4 Light Barrel






The 14.5” N4 barrel was tested in the same manner as described above. Three 10-shot groups fired from 100 yards using match grade hand-loads had extreme spreads of:

1.029”
1.360”
1.275”

for a 10-shot group average of 1.22”. As above, I over-layed the three 10-shot groups on each other using RSI Shooting lab to form a 30-shot composite group. The mean radius for that composite group was 0.37”.




…..

Thank you, this is the kind of information I was hoping for.

[Molon]

Molon , you are quite knowledgeable about AR15's but do you think there is a possibility that the post you quoted is not the only one I was referring to? Here that same person refers to the post you picked as my sole source.



So yeah, he did say that, part in your post and part in mine. I fully agree with him being the owner of both 10.3 DD MK18 upper and a 10.5" PSA CHF upper and they both group fine. Only difference is that the PSA barrel is less gassy with .070 gasport compared to the DD barrels .085 gasport. The DD BCG has a better finish and the staking looks cleaner.

I highly doubt that the full-auto M4's he puts out on the line are going to have his best barrels. If I were him I would also use barely serviceable barrels for people to finish burning out since they wont be trying for groups while rockin at full tilt.

My apologies. You are correct. I should not have assumed that was the only post that you were referring to.

[jerrysimons]

Thanks Molon! You are an inspiration. I have a Noveske Skinny, N4 Light Recce, and Recon barreled rifles. It is nice to see scientific data from a shooter that can push these barrels to their performance potential.